From 904cf94648d69435b2062d7929d450f58cfb8533 Mon Sep 17 00:00:00 2001
From: David Cermak <cermak@espressif.com>
Date: Sun, 7 Mar 2021 19:43:45 +0100
Subject: [PATCH] Implement perfect forwarding for command lib

---
 esp_modem/CMakeLists.txt                      |  8 +-
 .../simple_cxx_client/main/simple_client.cpp  | 29 ++++--
 .../include/cxx_include/esp_modem_api.hpp     | 15 ++-
 .../include/cxx_include/esp_modem_cmux.hpp    | 45 +++++++++
 .../cxx_include/esp_modem_command_library.hpp | 27 +++++
 .../include/cxx_include/esp_modem_dce.hpp     | 63 +++++++++---
 .../cxx_include/esp_modem_dce_commands.hpp    | 40 --------
 .../cxx_include/esp_modem_dce_commands_if.hpp |  9 --
 .../cxx_include/esp_modem_dce_module.hpp      | 70 +++++++++++++
 .../cxx_include/esp_modem_device_factory.hpp  |  5 -
 .../include/cxx_include/esp_modem_dte.hpp     | 99 ++-----------------
 .../{ppp_netif.hpp => esp_modem_netif.hpp}    |  8 +-
 ...l_objects.hpp => esp_modem_primitives.hpp} |  8 +-
 .../cxx_include/esp_modem_terminal.hpp        | 43 ++++++++
 .../include/cxx_include/esp_modem_types.hpp   | 43 ++++++++
 .../cxx_include/esp_modem_uart_terminal.hpp   | 10 --
 esp_modem/include/esp_modem_api.h             | 33 +++++++
 .../generate/esp_modem_command_declare.inc    | 73 ++++++++++++++
 .../uart_terminal.hpp                         |  0
 esp_modem/src/esp_modem_api.cpp               | 80 ++++++++++++++-
 .../esp_modem_command_library.cpp}            | 70 +++++--------
 esp_modem/src/esp_modem_dce.cpp               | 33 -------
 esp_modem/src/esp_modem_device.cpp            | 46 ---------
 esp_modem/src/esp_modem_device_factory.cpp    | 10 --
 esp_modem/src/esp_modem_dte.cpp               |  5 +-
 esp_modem/src/esp_modem_factory.cpp           | 21 ++++
 esp_modem/src/esp_modem_modules.cpp           | 23 +++++
 .../{ppp_netif.cpp => esp_modem_netif.cpp}    |  5 +-
 esp_modem/src/esp_modem_uart.cpp              |  3 -
 29 files changed, 586 insertions(+), 338 deletions(-)
 create mode 100644 esp_modem/include/cxx_include/esp_modem_cmux.hpp
 create mode 100644 esp_modem/include/cxx_include/esp_modem_command_library.hpp
 delete mode 100644 esp_modem/include/cxx_include/esp_modem_dce_commands.hpp
 delete mode 100644 esp_modem/include/cxx_include/esp_modem_dce_commands_if.hpp
 create mode 100644 esp_modem/include/cxx_include/esp_modem_dce_module.hpp
 delete mode 100644 esp_modem/include/cxx_include/esp_modem_device_factory.hpp
 rename esp_modem/include/cxx_include/{ppp_netif.hpp => esp_modem_netif.hpp} (83%)
 rename esp_modem/include/cxx_include/{terminal_objects.hpp => esp_modem_primitives.hpp} (93%)
 create mode 100644 esp_modem/include/cxx_include/esp_modem_terminal.hpp
 create mode 100644 esp_modem/include/cxx_include/esp_modem_types.hpp
 delete mode 100644 esp_modem/include/cxx_include/esp_modem_uart_terminal.hpp
 create mode 100644 esp_modem/include/esp_modem_api.h
 create mode 100644 esp_modem/include/generate/esp_modem_command_declare.inc
 rename esp_modem/{include/cxx_include => private_include}/uart_terminal.hpp (100%)
 rename esp_modem/{include/cxx_include/esp_modem_commands.hpp => src/esp_modem_command_library.cpp} (65%)
 delete mode 100644 esp_modem/src/esp_modem_dce.cpp
 delete mode 100644 esp_modem/src/esp_modem_device.cpp
 delete mode 100644 esp_modem/src/esp_modem_device_factory.cpp
 create mode 100644 esp_modem/src/esp_modem_factory.cpp
 create mode 100644 esp_modem/src/esp_modem_modules.cpp
 rename esp_modem/src/{ppp_netif.cpp => esp_modem_netif.cpp} (97%)

diff --git a/esp_modem/CMakeLists.txt b/esp_modem/CMakeLists.txt
index 1724bf949..ef441d9cd 100644
--- a/esp_modem/CMakeLists.txt
+++ b/esp_modem/CMakeLists.txt
@@ -9,12 +9,12 @@ set(srcs "src/esp_modem.c"
         "src/esp_sim7600.c"
         "src/esp_bg96.c"
         "src/esp_modem_dte.cpp"
-        "src/ppp_netif.cpp"
+        "src/esp_modem_netif.cpp"
         "src/esp_modem_api.cpp"
-        "src/esp_modem_dce.cpp"
-        "src/esp_modem_device.cpp"
-        "src/esp_modem_device_factory.cpp"
+        "src/esp_modem_factory.cpp"
         "src/esp_modem_cmux.cpp"
+        "src/esp_modem_command_library.cpp"
+        "src/esp_modem_modules.cpp"
         "src/esp_modem_uart.cpp")
 
 set(include_dirs "include")
diff --git a/esp_modem/examples/simple_cxx_client/main/simple_client.cpp b/esp_modem/examples/simple_cxx_client/main/simple_client.cpp
index 3f17ca6af..e426019ee 100644
--- a/esp_modem/examples/simple_cxx_client/main/simple_client.cpp
+++ b/esp_modem/examples/simple_cxx_client/main/simple_client.cpp
@@ -16,7 +16,7 @@
 #include "esp_modem_netif.h"
 #include "esp_log.h"
 #include "cxx_include/esp_modem_dte.hpp"
-#include "cxx_include/uart_terminal.hpp"
+
 #include "cxx_include/esp_modem_api.hpp"
 
 #define BROKER_URL "mqtt://mqtt.eclipseprojects.io"
@@ -266,7 +266,7 @@ static void modem_test_app(esp_modem_dte_config_t *dte_config, esp_modem_dce_con
     uint8_t data[32] = {};
     int actual_len = 0;
     auto uart_dte = create_uart_dte(dte_config);
-    uart_dte->set_mode(dte_mode::UNDEF);
+    uart_dte->set_mode(modem_mode::UNDEF);
     uart_dte->command("+++", [&](uint8_t *data, size_t len) {
         std::string response((char*)data, len);
         ESP_LOGI("in the lambda", "len=%d data %s", len, (char*)data);
@@ -293,14 +293,15 @@ static void modem_test_app(esp_modem_dte_config_t *dte_config, esp_modem_dce_con
     assert(esp_netif);
 
     std::string apn = "internet";
-    auto device = create_device(uart_dte, apn);
-    bool pin_ok = true;
-    if (device->read_pin(pin_ok) == command_result::OK && !pin_ok) {
-        throw_if_false(device->set_pin("1234") == command_result::OK, "Cannot set PIN!");
-    }
+//    auto device = create_generic_module(uart_dte, apn);
+    auto device = create_SIM7600_module(uart_dte, apn);
+//    bool pin_ok = true;
+//    if (device->read_pin(pin_ok) == command_result::OK && !pin_ok) {
+//        throw_if_false(device->set_pin("1234") == command_result::OK, "Cannot set PIN!");
+//    }
 
 //
-//    std::string number;
+    std::string number;
 //    std::cout << "----" << std::endl;
 //    device->get_imsi(number);
 //    std::cout << "----" << std::endl;
@@ -312,7 +313,14 @@ static void modem_test_app(esp_modem_dte_config_t *dte_config, esp_modem_dce_con
 //    device->get_module_name(number);
 //    std::cout << "|" << number << "|" << std::endl;
 //    std::cout << "----" << std::endl;
-    auto my_dce = create_dce(uart_dte, device, esp_netif);
+//    auto my_dce = create_generic_module_dce(uart_dte, device, esp_netif);
+    auto my_dce = create_SIM7600_dce_from_module(uart_dte, device, esp_netif);
+    my_dce->get_module_name(number);
+    std::cout << "|" << number << "|" << std::endl;
+    bool pin_ok = true;
+    if (my_dce->read_pin(pin_ok) == command_result::OK && !pin_ok) {
+        throw_if_false(my_dce->set_pin("1234") == command_result::OK, "Cannot set PIN!");
+    }
 
 //    return;
 //    my_dce->set_cmux();
@@ -326,6 +334,9 @@ static void modem_test_app(esp_modem_dte_config_t *dte_config, esp_modem_dce_con
 //    uart_dte->send_cmux_command(2, "AT+CPIN?");
 //    return;
 
+    my_dce->get_module_name(number);
+    my_dce->set_data_mode();
+
     my_dce->command("AT+CPIN?\r", [&](uint8_t *data, size_t len) {
         std::string response((char*)data, len);
         ESP_LOGI("in the lambda", "len=%d data %s", len, (char*)data);
diff --git a/esp_modem/include/cxx_include/esp_modem_api.hpp b/esp_modem/include/cxx_include/esp_modem_api.hpp
index b6c5dd24d..047c4d034 100644
--- a/esp_modem/include/cxx_include/esp_modem_api.hpp
+++ b/esp_modem/include/cxx_include/esp_modem_api.hpp
@@ -2,13 +2,24 @@
 
 #include <memory>
 #include "cxx_include/esp_modem_dce.hpp"
-#include "cxx_include/esp_modem_device_factory.hpp"
+#include "cxx_include/esp_modem_dce_module.hpp"
 
 class DTE;
+class GenericModule;
+class SIM7600;
+class SIM800;
+class BG96;
 struct dte_config;
 typedef struct esp_netif_obj esp_netif_t;
 
 std::shared_ptr<DTE> create_uart_dte(const dte_config *config);
 
-std::unique_ptr<DCE> create_dce(const std::shared_ptr<DTE>& dte, const std::shared_ptr<DeviceIf>& dev, esp_netif_t *netif);
 
+std::shared_ptr<GenericModule> create_generic_module(const std::shared_ptr<DTE>& dte, std::string &apn);
+std::shared_ptr<SIM7600> create_SIM7600_module(const std::shared_ptr<DTE>& dte, std::string &apn);
+
+std::unique_ptr<DCE<GenericModule>> create_generic_dce_from_module(const std::shared_ptr<DTE>& dte, const std::shared_ptr<GenericModule>& dev, esp_netif_t *netif);
+std::unique_ptr<DCE<SIM7600>> create_SIM7600_dce_from_module(const std::shared_ptr<DTE>& dte, const std::shared_ptr<SIM7600>& dev, esp_netif_t *netif);
+
+
+std::unique_ptr<DCE<SIM7600>> create_SIM7600_dce(const std::shared_ptr<DTE>& dte, esp_netif_t *netif, std::string &apn);
diff --git a/esp_modem/include/cxx_include/esp_modem_cmux.hpp b/esp_modem/include/cxx_include/esp_modem_cmux.hpp
new file mode 100644
index 000000000..95ba4e9ef
--- /dev/null
+++ b/esp_modem/include/cxx_include/esp_modem_cmux.hpp
@@ -0,0 +1,45 @@
+//
+// Created by david on 3/8/21.
+//
+
+#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_CMUX_HPP
+#define SIMPLE_CXX_CLIENT_ESP_MODEM_CMUX_HPP
+
+enum class cmux_state {
+    INIT,
+    HEADER,
+    PAYLOAD,
+    FOOTER,
+    RECOVER,
+};
+
+class CMUXedTerminal: public Terminal {
+public:
+    explicit CMUXedTerminal(std::unique_ptr<Terminal> t, std::unique_ptr<uint8_t[]> b, size_t buff_size):
+            term(std::move(t)), buffer(std::move(b)) {}
+    ~CMUXedTerminal() override = default;
+    void setup_cmux();
+    void set_data_cb(std::function<bool(size_t len)> f) override {}
+    int write(uint8_t *data, size_t len) override;
+    int read(uint8_t *data, size_t len)  override { return term->read(data, len); }
+    void start() override;
+    void stop() override {}
+private:
+    static bool process_cmux_recv(size_t len);
+    void send_sabm(size_t i);
+    std::unique_ptr<Terminal> term;
+    cmux_state state;
+    uint8_t dlci;
+    uint8_t type;
+    size_t payload_len;
+    uint8_t frame_header[6];
+    size_t frame_header_offset;
+    size_t buffer_size;
+    size_t consumed;
+    std::unique_ptr<uint8_t[]> buffer;
+    bool on_cmux(size_t len);
+
+};
+
+
+#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_CMUX_HPP
diff --git a/esp_modem/include/cxx_include/esp_modem_command_library.hpp b/esp_modem/include/cxx_include/esp_modem_command_library.hpp
new file mode 100644
index 000000000..9d7d823f7
--- /dev/null
+++ b/esp_modem/include/cxx_include/esp_modem_command_library.hpp
@@ -0,0 +1,27 @@
+//
+// Created by david on 3/2/21.
+//
+
+#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_COMMAND_LIBRARY_HPP
+#define SIMPLE_CXX_CLIENT_ESP_MODEM_COMMAND_LIBRARY_HPP
+
+#include "esp_modem_dte.hpp"
+#include "esp_modem_dce_module.hpp"
+#include "esp_modem_types.hpp"
+#include "generate/esp_modem_command_declare.inc"
+
+namespace esp_modem {
+namespace dce_commands {
+
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, TEMPLATE_ARG, MUX_ARG, ...) \
+        return_type name(CommandableIf *t, ## __VA_ARGS__);
+
+        DECLARE_ALL_COMMAND_APIS(forwards name(...) { device->name(...); } )
+
+#undef ESP_MODEM_DECLARE_DCE_COMMAND
+
+} // dce_commands
+} // esp_modem
+
+
+#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_COMMAND_LIBRARY_HPP
diff --git a/esp_modem/include/cxx_include/esp_modem_dce.hpp b/esp_modem/include/cxx_include/esp_modem_dce.hpp
index 9102e32db..9fa6b6f50 100644
--- a/esp_modem/include/cxx_include/esp_modem_dce.hpp
+++ b/esp_modem/include/cxx_include/esp_modem_dce.hpp
@@ -1,28 +1,65 @@
 #pragma once
-#include "cxx_include/esp_modem_dce_commands_if.hpp"
+#include "cxx_include/esp_modem_netif.hpp"
+#include "generate/esp_modem_command_declare.inc"
 
+template<class SpecificModule>
 class DCE {
+    static_assert(std::is_base_of<ModuleIf, SpecificModule>::value, "DCE must be instantiated with Module class only");
 public:
-    explicit DCE(const std::shared_ptr<DTE>& d, std::shared_ptr<DeviceIf> device, esp_netif_t * netif);
+    explicit DCE(const std::shared_ptr<DTE>& dte, std::shared_ptr<SpecificModule> device, esp_netif_t * netif):
+        dce_dte(dte), device(std::move(device)), ppp_netif(dte, netif)
+    { }
     void set_data() {
-//        command("AT+CGDCONT=1,\"IP\",\"internet\"\r", [&](uint8_t *data, size_t len) {
-//            return command_result::OK;
-//        }, 1000);
-//        command("ATD*99***1#\r", [&](uint8_t *data, size_t len) {
-//            return command_result::OK;
-//        }, 1000);
         device->setup_data_mode();
-        device->set_mode(dte_mode::DATA_MODE);
-        dce_dte->set_mode(dte_mode::DATA_MODE);
+        device->set_mode(modem_mode::DATA_MODE);
+        dce_dte->set_mode(modem_mode::DATA_MODE);
         ppp_netif.start();
     }
-    void exit_data();
+    void exit_data() {
+        ppp_netif.stop();
+        device->set_mode(modem_mode::COMMAND_MODE);
+//        uint8_t* data;
+        dce_dte->set_data_cb([&](size_t len) -> bool {
+//            auto actual_len = dce_dte->read(&data, 64);
+//            ESP_LOG_BUFFER_HEXDUMP("esp-modem: debug_data", data, actual_len, ESP_LOG_INFO);
+            return false;
+        });
+        ppp_netif.wait_until_ppp_exits();
+        dce_dte->set_data_cb(nullptr);
+        dce_dte->set_mode(modem_mode::COMMAND_MODE);
+    }
+
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, TEMPLATE_ARG, MUX_ARG, ...) \
+    template <typename ...Agrs> \
+    return_type name(Agrs&&... args)   \
+    {   \
+        return device->name(std::forward<Agrs>(args)...); \
+    }
+
+    DECLARE_ALL_COMMAND_APIS(forwards name(...) { device->name(...); } )
+
+#undef ESP_MODEM_DECLARE_DCE_COMMAND
+
+
+//    template <typename ...Params>
+//    command_result get_module_name(Params&&... params)
+//    {
+//        return device->get_module_name(std::forward<Params>(params)...);
+//    }
+//    template <typename ...Params>
+//    command_result set_data_mode(Params&&... params)
+//    {
+//        return device->set_data_mode(std::forward<Params>(params)...);
+//    }
+
+
     command_result command(const std::string& command, got_line_cb got_line, uint32_t time_ms) {
         return dce_dte->command(command, got_line, time_ms);
     }
-    void set_cmux();
+    void set_cmux() {    device->set_mode(modem_mode::CMUX_MODE);
+        dce_dte->set_mode(modem_mode::CMUX_MODE); }
 private:
     std::shared_ptr<DTE> dce_dte;
-    std::shared_ptr<DeviceIf> device;
+    std::shared_ptr<SpecificModule> device;
     PPP ppp_netif;
 };
\ No newline at end of file
diff --git a/esp_modem/include/cxx_include/esp_modem_dce_commands.hpp b/esp_modem/include/cxx_include/esp_modem_dce_commands.hpp
deleted file mode 100644
index 74e6564f5..000000000
--- a/esp_modem/include/cxx_include/esp_modem_dce_commands.hpp
+++ /dev/null
@@ -1,40 +0,0 @@
-#pragma once
-#include "cxx_include/esp_modem_dce_commands_if.hpp"
-#include <memory>
-#include <utility>
-
-struct PdpContext {
-    PdpContext(std::string& apn): context_id(1), protocol_type("IP"), apn(apn) {}
-    size_t context_id;
-    std::string protocol_type;
-    std::string apn;
-};
-
-enum class command_result;
-class DTE;
-
-class Device: public DeviceIf {
-public:
-    explicit Device(std::shared_ptr<DTE> dte, std::unique_ptr<PdpContext> pdp):
-        dte(std::move(dte)), pdp(std::move(pdp)) {}
-    bool setup_data_mode() override;
-    bool set_mode(dte_mode mode) override;
-
-    command_result set_echo(bool on);
-    command_result set_data_mode();
-    command_result resume_data_mode();
-    command_result set_pdp_context(PdpContext& pdp_context);
-    command_result set_command_mode();
-    command_result set_cmux();
-    command_result get_imsi(std::string& imsi_number);
-    command_result set_pin(const std::string& pin);
-    command_result read_pin(bool& pin_ok);
-    command_result get_imei(std::string& imei);
-    command_result get_module_name(std::string& imei);
-
-private:
-    std::shared_ptr<DTE> dte;
-    std::unique_ptr<PdpContext> pdp;
-};
-
-
diff --git a/esp_modem/include/cxx_include/esp_modem_dce_commands_if.hpp b/esp_modem/include/cxx_include/esp_modem_dce_commands_if.hpp
deleted file mode 100644
index b2d5d0841..000000000
--- a/esp_modem/include/cxx_include/esp_modem_dce_commands_if.hpp
+++ /dev/null
@@ -1,9 +0,0 @@
-#pragma once
-
-enum class dte_mode;
-
-class DeviceIf {
-public:
-    virtual bool setup_data_mode() = 0;
-    virtual bool set_mode(dte_mode mode) = 0;
-};
\ No newline at end of file
diff --git a/esp_modem/include/cxx_include/esp_modem_dce_module.hpp b/esp_modem/include/cxx_include/esp_modem_dce_module.hpp
new file mode 100644
index 000000000..1b048ea4f
--- /dev/null
+++ b/esp_modem/include/cxx_include/esp_modem_dce_module.hpp
@@ -0,0 +1,70 @@
+#pragma once
+#include <memory>
+#include <utility>
+#include "generate/esp_modem_command_declare.inc"
+#include "cxx_include/esp_modem_command_library.hpp"
+#include "cxx_include/esp_modem_types.hpp"
+
+enum class command_result;
+class DTE;
+
+class GenericModule: public ModuleIf {
+public:
+    explicit GenericModule(std::shared_ptr<DTE> dte, std::unique_ptr<PdpContext> pdp):
+            dte(std::move(dte)), pdp(std::move(pdp)) {}
+
+    bool setup_data_mode() override
+    {
+        if (set_echo(false) != command_result::OK)
+            return false;
+        if (set_pdp_context(*pdp) != command_result::OK)
+            return false;
+        return true;
+    }
+
+    bool set_mode(modem_mode mode) override
+    {
+        if (mode == modem_mode::DATA_MODE) {
+            if (set_data_mode() != command_result::OK)
+                return resume_data_mode() == command_result::OK;
+            return true;
+        } else if (mode == modem_mode::COMMAND_MODE) {
+            return set_command_mode() == command_result::OK;
+        } else if (mode == modem_mode::CMUX_MODE) {
+            return set_cmux() == command_result::OK;
+        }
+        return true;
+    }
+
+
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, TEMPLATE_ARG, MUX_ARG, ...) \
+    template <typename ...Agrs> \
+    return_type name(Agrs&&... args) { return esp_modem::dce_commands::name(dte.get(), std::forward<Agrs>(args)...); }
+
+    DECLARE_ALL_COMMAND_APIS(return_type name(...); )
+
+#undef ESP_MODEM_DECLARE_DCE_COMMAND
+
+
+protected:
+    std::shared_ptr<DTE> dte;
+    std::unique_ptr<PdpContext> pdp;
+};
+
+// Definitions of other modules
+class SIM7600: public GenericModule {
+    using GenericModule::GenericModule;
+public:
+    command_result get_module_name(std::string& name);
+};
+
+class SIM800: public GenericModule {
+    using GenericModule::GenericModule;
+public:
+    command_result get_module_name(std::string& name);
+};
+
+class BG96: public GenericModule {
+public:
+    command_result get_module_name(std::string& name);
+};
diff --git a/esp_modem/include/cxx_include/esp_modem_device_factory.hpp b/esp_modem/include/cxx_include/esp_modem_device_factory.hpp
deleted file mode 100644
index 093dc3deb..000000000
--- a/esp_modem/include/cxx_include/esp_modem_device_factory.hpp
+++ /dev/null
@@ -1,5 +0,0 @@
-#pragma once
-
-#include "cxx_include/esp_modem_dce_commands.hpp"
-//std::shared_ptr<DeviceIf> create_device(const std::shared_ptr<DTE>& dte, std::string &apn);
-std::shared_ptr<Device> create_device(const std::shared_ptr<DTE>& dte, std::string &apn);
\ No newline at end of file
diff --git a/esp_modem/include/cxx_include/esp_modem_dte.hpp b/esp_modem/include/cxx_include/esp_modem_dte.hpp
index 34c3c8fb0..5987e38fd 100644
--- a/esp_modem/include/cxx_include/esp_modem_dte.hpp
+++ b/esp_modem/include/cxx_include/esp_modem_dte.hpp
@@ -1,6 +1,5 @@
 #ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_DTE_HPP
 #define SIMPLE_CXX_CLIENT_ESP_MODEM_DTE_HPP
-
 #include <memory>
 #include <functional>
 #include <exception>
@@ -8,94 +7,16 @@
 #include <cstdint>
 #include <utility>
 #include "esp_err.h"
-#include "terminal_objects.hpp"
-#include "ppp_netif.hpp"
-#include <array>
+#include "cxx_include/esp_modem_primitives.hpp"
+#include "cxx_include/esp_modem_terminal.hpp"
+#include "cxx_include/esp_modem_cmux.hpp"
+#include "cxx_include/esp_modem_types.hpp"
 
-enum class terminal_error {
-    BUFFER_OVERFLOW,
-    CHECKSUM_ERROR,
-    UNEXPECTED_CONTROL_FLOW,
-};
-
-class Terminal {
-public:
-    virtual ~Terminal() = default;
-    virtual void set_data_cb(std::function<bool(size_t len)> f) { on_data = std::move(f); }
-    void set_error_cb(std::function<void(terminal_error)> f) { on_error = std::move(f); }
-    virtual int write(uint8_t *data, size_t len) = 0;
-    virtual int read(uint8_t *data, size_t len) = 0;
-    virtual void start() = 0;
-    virtual void stop() = 0;
-
-protected:
-    std::function<bool(size_t len)> on_data;
-    std::function<void(terminal_error)> on_error;
-};
-
-
-enum class cmux_state {
-    INIT,
-    HEADER,
-    PAYLOAD,
-    FOOTER,
-    RECOVER,
-};
-
-class CMUXedTerminal: public Terminal {
-public:
-    explicit CMUXedTerminal(std::unique_ptr<Terminal> t, std::unique_ptr<uint8_t[]> b, size_t buff_size):
-            term(std::move(t)), buffer(std::move(b)) {}
-    ~CMUXedTerminal() override = default;
-    void setup_cmux();
-    void set_data_cb(std::function<bool(size_t len)> f) override {}
-    int write(uint8_t *data, size_t len) override;
-    int read(uint8_t *data, size_t len)  override { return term->read(data, len); }
-    void start() override;
-    void stop() override {}
-private:
-    static bool process_cmux_recv(size_t len);
-    void send_sabm(size_t i);
-    std::unique_ptr<Terminal> term;
-    cmux_state state;
-    uint8_t dlci;
-    uint8_t type;
-    size_t payload_len;
-    uint8_t frame_header[6];
-    size_t frame_header_offset;
-    size_t buffer_size;
-    size_t consumed;
-    std::unique_ptr<uint8_t[]> buffer;
-    bool on_cmux(size_t len);
-
-};
-
-
-enum class dte_mode {
-    UNDEF,
-    COMMAND_MODE,
-    DATA_MODE,
-    CMUX_MODE
-};
-
-enum class command_result {
-    OK,
-    FAIL,
-    TIMEOUT
-};
 
 const int DTE_BUFFER_SIZE = 1024;
 
 
-struct CMUXHelper {
-    void send_sabm(size_t dlci);
-};
-
-
-
-typedef std::function<command_result(uint8_t *data, size_t len)> got_line_cb;
-
-class DTE {
+class DTE: public CommandableIf {
 public:
  explicit DTE(std::unique_ptr<Terminal> t);
   ~DTE() = default;
@@ -120,15 +41,15 @@ public:
 //    std::shared_ptr<uint8_t[]> get_buffer() { return buffer;}
     void start() { term->start(); }
     void data_mode_closed() { term->stop(); }
-  void set_mode(dte_mode m) {
+  void set_mode(modem_mode m) {
         term->start(); mode = m;
-        if (m == dte_mode::DATA_MODE) {
+        if (m == modem_mode::DATA_MODE) {
             term->set_data_cb(on_data);
-        } else if (m == dte_mode::CMUX_MODE) {
+        } else if (m == modem_mode::CMUX_MODE) {
             setup_cmux();
         }
     }
-    command_result command(const std::string& command, got_line_cb got_line, uint32_t time_ms);
+    command_result command(const std::string& command, got_line_cb got_line, uint32_t time_ms) override;
 //    std::shared_ptr<uint8_t[]> buffer;
 
     void send_cmux_command(uint8_t i, const std::string& command);
@@ -145,7 +66,7 @@ private:
     std::unique_ptr<uint8_t[]> buffer;
     std::unique_ptr<Terminal> term;
 //    got_line_cb on_line;
-    dte_mode mode;
+    modem_mode mode;
     signal_group signal;
     std::function<bool(size_t len)> on_data;
 
diff --git a/esp_modem/include/cxx_include/ppp_netif.hpp b/esp_modem/include/cxx_include/esp_modem_netif.hpp
similarity index 83%
rename from esp_modem/include/cxx_include/ppp_netif.hpp
rename to esp_modem/include/cxx_include/esp_modem_netif.hpp
index 956162400..f283f0281 100644
--- a/esp_modem/include/cxx_include/ppp_netif.hpp
+++ b/esp_modem/include/cxx_include/esp_modem_netif.hpp
@@ -2,11 +2,11 @@
 // Created by david on 2/26/21.
 //
 
-#ifndef SIMPLE_CXX_CLIENT_PPP_NETIF_HPP
-#define SIMPLE_CXX_CLIENT_PPP_NETIF_HPP
+#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_NETIF_HPP
+#define SIMPLE_CXX_CLIENT_ESP_MODEM_NETIF_HPP
 
 #include "esp_netif.h"
-#include "cxx_include/terminal_objects.hpp"
+#include "cxx_include/esp_modem_primitives.hpp"
 
 class DTE;
 class PPP;
@@ -42,4 +42,4 @@ private:
 };
 
 
-#endif //SIMPLE_CXX_CLIENT_PPP_NETIF_HPP
+#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_NETIF_HPP
diff --git a/esp_modem/include/cxx_include/terminal_objects.hpp b/esp_modem/include/cxx_include/esp_modem_primitives.hpp
similarity index 93%
rename from esp_modem/include/cxx_include/terminal_objects.hpp
rename to esp_modem/include/cxx_include/esp_modem_primitives.hpp
index 66223400b..793a0615a 100644
--- a/esp_modem/include/cxx_include/terminal_objects.hpp
+++ b/esp_modem/include/cxx_include/esp_modem_primitives.hpp
@@ -2,8 +2,8 @@
 // Created by david on 2/26/21.
 //
 
-#ifndef SIMPLE_CXX_CLIENT_TERMINAL_OBJECTS_HPP
-#define SIMPLE_CXX_CLIENT_TERMINAL_OBJECTS_HPP
+#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_PRIMITIVES_HPP
+#define SIMPLE_CXX_CLIENT_ESP_MODEM_PRIMITIVES_HPP
 #include "freertos/FreeRTOS.h"
 #include "freertos/event_groups.h"
 #include "freertos/semphr.h"
@@ -49,7 +49,7 @@ static inline void throw_if_esp_fail(esp_err_t err)
 struct Lock {
     explicit Lock(): lock(nullptr)
     {
-        lock = xSemaphoreCreateMutex();
+        lock = xSemaphoreCreateRecursiveMutex();
         throw_if_false(lock != nullptr, "create signal event group failed");
     }
     ~Lock() { vSemaphoreDelete(lock); }
@@ -111,4 +111,4 @@ struct signal_group {
     EventGroupHandle_t event_group;
 };
 
-#endif //SIMPLE_CXX_CLIENT_TERMINAL_OBJECTS_HPP
+#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_PRIMITIVES_HPP
diff --git a/esp_modem/include/cxx_include/esp_modem_terminal.hpp b/esp_modem/include/cxx_include/esp_modem_terminal.hpp
new file mode 100644
index 000000000..8cce80618
--- /dev/null
+++ b/esp_modem/include/cxx_include/esp_modem_terminal.hpp
@@ -0,0 +1,43 @@
+//
+// Created by david on 3/3/21.
+//
+
+#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_TERMINAL_HPP
+#define SIMPLE_CXX_CLIENT_ESP_MODEM_TERMINAL_HPP
+
+
+#include <memory>
+#include <functional>
+#include <exception>
+#include <cstddef>
+#include <cstdint>
+#include <utility>
+#include "esp_err.h"
+#include "esp_modem_primitives.hpp"
+
+
+enum class terminal_error {
+    BUFFER_OVERFLOW,
+    CHECKSUM_ERROR,
+    UNEXPECTED_CONTROL_FLOW,
+};
+
+class Terminal {
+public:
+    virtual ~Terminal() = default;
+    virtual void set_data_cb(std::function<bool(size_t len)> f) { on_data = std::move(f); }
+    void set_error_cb(std::function<void(terminal_error)> f) { on_error = std::move(f); }
+    virtual int write(uint8_t *data, size_t len) = 0;
+    virtual int read(uint8_t *data, size_t len) = 0;
+    virtual void start() = 0;
+    virtual void stop() = 0;
+    virtual size_t max_virtual_terms() { return 1; }
+
+protected:
+    std::function<bool(size_t len)> on_data;
+    std::function<void(terminal_error)> on_error;
+};
+
+
+
+#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_TERMINAL_HPP
diff --git a/esp_modem/include/cxx_include/esp_modem_types.hpp b/esp_modem/include/cxx_include/esp_modem_types.hpp
new file mode 100644
index 000000000..87ddbce35
--- /dev/null
+++ b/esp_modem/include/cxx_include/esp_modem_types.hpp
@@ -0,0 +1,43 @@
+//
+// Created by david on 3/8/21.
+//
+
+#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_TYPES_HPP
+#define SIMPLE_CXX_CLIENT_ESP_MODEM_TYPES_HPP
+
+
+enum class modem_mode {
+    UNDEF,
+    COMMAND_MODE,
+    DATA_MODE,
+    CMUX_MODE
+};
+
+enum class command_result {
+    OK,
+    FAIL,
+    TIMEOUT
+};
+
+typedef std::function<command_result(uint8_t *data, size_t len)> got_line_cb;
+
+struct PdpContext {
+    explicit PdpContext(std::string& apn): context_id(1), protocol_type("IP"), apn(apn) {}
+    size_t context_id;
+    std::string protocol_type;
+    std::string apn;
+};
+
+
+class CommandableIf {
+public:
+    virtual command_result command(const std::string& command, got_line_cb got_line, uint32_t time_ms) = 0;
+};
+
+class ModuleIf {
+public:
+    virtual bool setup_data_mode() = 0;
+    virtual bool set_mode(modem_mode mode) = 0;
+};
+
+#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_TYPES_HPP
diff --git a/esp_modem/include/cxx_include/esp_modem_uart_terminal.hpp b/esp_modem/include/cxx_include/esp_modem_uart_terminal.hpp
deleted file mode 100644
index 84c4c7b3a..000000000
--- a/esp_modem/include/cxx_include/esp_modem_uart_terminal.hpp
+++ /dev/null
@@ -1,10 +0,0 @@
-//
-// Created by david on 3/3/21.
-//
-
-#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_UART_TERMINAL_HPP
-#define SIMPLE_CXX_CLIENT_ESP_MODEM_UART_TERMINAL_HPP
-
-
-
-#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_UART_TERMINAL_HPP
diff --git a/esp_modem/include/esp_modem_api.h b/esp_modem/include/esp_modem_api.h
new file mode 100644
index 000000000..6482e35b1
--- /dev/null
+++ b/esp_modem/include/esp_modem_api.h
@@ -0,0 +1,33 @@
+//
+// Created by david on 3/8/21.
+//
+
+#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_API_H
+#define SIMPLE_CXX_CLIENT_ESP_MODEM_API_H
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct esp_modem_dce_wrap esp_modem_t;
+
+esp_modem_t *esp_modem_new(const dte_config *config, esp_netif_t *netif, const char* apn);
+
+void esp_modem_destroy(esp_modem_t * dce);
+
+
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, TEMPLATE_ARG, MUX_ARG, ...) \
+        esp_err_t esp_modem_ ## name(esp_modem_t *dce, ##__VA_ARGS__);
+
+DECLARE_ALL_COMMAND_APIS(declares esp_modem_<API>(esp_modem_t * dce, ...);)
+
+#undef ESP_MODEM_DECLARE_DCE_COMMAND
+
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_API_H
diff --git a/esp_modem/include/generate/esp_modem_command_declare.inc b/esp_modem/include/generate/esp_modem_command_declare.inc
new file mode 100644
index 000000000..13b17dc9b
--- /dev/null
+++ b/esp_modem/include/generate/esp_modem_command_declare.inc
@@ -0,0 +1,73 @@
+//
+// Created by david on 3/7/21.
+//
+
+#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_COMMAND_DECLARE_INC
+#define SIMPLE_CXX_CLIENT_ESP_MODEM_COMMAND_DECLARE_INC
+
+#ifdef __cplusplus
+#define STRING_IN const std::string&
+#define STRING_OUT std::string&
+#else
+#define STRING_IN const char*
+#define STRING_OUT char*
+#endif
+
+
+#define ESP_MODEM_DEFINE_DCE_COMMAND(...) ESP_MODEM_DECLARE_DCE_COMMAND(##__VA_ARGS__)
+#define DEFINE_ALL_COMMAND_APIS() DECLARE_ALL_COMMAND_APIS()
+
+#define DECLARE_ALL_COMMAND_APIS(...) \
+/**
+ * @brief Sends the supplied PIN code
+ *
+ * @param pin Pin
+ */ \
+    \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_pin,  command_result, TEMPLATE_ARG, MUX_ARG, STRING_IN) \
+/**
+ * @brief Checks if the SIM needs a PIN
+ *
+ * @param[out] pin_ok Pin
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(read_pin, command_result, TEMPLATE_ARG, MUX_ARG, bool& pin_ok)           \
+    \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_echo, command_result, TEMPLATE_ARG, MUX_ARG, bool on)           \
+    \
+ESP_MODEM_DECLARE_DCE_COMMAND(resume_data_mode, command_result, TEMPLATE_ARG, MUX_ARG)           \
+    \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_pdp_context, command_result, TEMPLATE_ARG, MUX_ARG, PdpContext& pdp_context) \
+    \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_command_mode, command_result, TEMPLATE_ARG, MUX_ARG) \
+    \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_cmux, command_result, TEMPLATE_ARG, MUX_ARG) \
+    \
+ESP_MODEM_DECLARE_DCE_COMMAND(get_imsi, command_result, TEMPLATE_ARG, MUX_ARG, std::string& imsi_number) \
+    \
+ESP_MODEM_DECLARE_DCE_COMMAND(get_imei, command_result, TEMPLATE_ARG, MUX_ARG, std::string& imsi_number) \
+    \
+/**
+ * @brief Reads the module name
+ *
+ * @param[out]  module name
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(get_module_name, command_result, TEMPLATE_ARG, MUX_ARG, std::string& name) \
+\
+/**
+ * @brief Sets the modem to data mode
+ *
+ */ \
+ESP_MODEM_DECLARE_DCE_COMMAND(set_data_mode, command_result, TEMPLATE_ARG, MUX_ARG)
+
+//  --- DCE command documentation starts here ---
+#ifdef GENERATE_DOCS
+// gcc -E -CC -P -DGENERATE_DOCS esp_modem_command_declare.inc | sed -n '/DCE command documentation/,//p'
+
+#define ESP_MODEM_DECLARE_DCE_COMMAND(name, return_type, TEMPLATE_ARG, MUX_ARG, ...) \
+return_type name (__VA_ARGS__);
+
+DECLARE_ALL_COMMAND_APIS()
+#endif
+
+
+#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_COMMAND_DECLARE_INC
diff --git a/esp_modem/include/cxx_include/uart_terminal.hpp b/esp_modem/private_include/uart_terminal.hpp
similarity index 100%
rename from esp_modem/include/cxx_include/uart_terminal.hpp
rename to esp_modem/private_include/uart_terminal.hpp
diff --git a/esp_modem/src/esp_modem_api.cpp b/esp_modem/src/esp_modem_api.cpp
index 29edb6a64..89a2982bc 100644
--- a/esp_modem/src/esp_modem_api.cpp
+++ b/esp_modem/src/esp_modem_api.cpp
@@ -2,9 +2,10 @@
 // Created by david on 3/3/21.
 //
 #include "cxx_include/esp_modem_dte.hpp"
-#include "cxx_include/uart_terminal.hpp"
+#include "uart_terminal.hpp"
 #include "esp_log.h"
 #include "cxx_include/esp_modem_api.hpp"
+#include "esp_modem_api.h"
 
 static const char *TAG = "dce_factory";
 struct PdpContext;
@@ -12,7 +13,6 @@ struct PdpContext;
 std::shared_ptr<DTE> create_uart_dte(const dte_config *config)
 {
     try {
-//        auto term = std::make_unique<dte>(std::make_unique<uart_terminal>(config));
         auto term = create_uart_terminal(config);
         return std::make_shared<DTE>(std::move(term));
     } catch (std::bad_alloc& e) {
@@ -27,10 +27,11 @@ std::shared_ptr<DTE> create_uart_dte(const dte_config *config)
 
 }
 
-std::unique_ptr<DCE> create_dce(const std::shared_ptr<DTE>& dte, const std::shared_ptr<DeviceIf>& dev, esp_netif_t *netif)
+template<typename SpecificModule>
+std::unique_ptr<DCE<SpecificModule>> create_dce(const std::shared_ptr<DTE>& dte, const std::shared_ptr<SpecificModule>& dev, esp_netif_t *netif)
 {
     try {
-        return std::make_unique<DCE>(dte, dev, netif);
+        return std::make_unique<DCE<SpecificModule>>(dte, dev, netif);
     } catch (std::bad_alloc& e) {
         ESP_LOGE(TAG, "Out of memory");
         return nullptr;
@@ -42,3 +43,74 @@ std::unique_ptr<DCE> create_dce(const std::shared_ptr<DTE>& dte, const std::shar
     }
 }
 
+std::unique_ptr<DCE<GenericModule>> create_generic_dce_from_module(const std::shared_ptr<DTE>& dte, const std::shared_ptr<GenericModule>& dev, esp_netif_t *netif)
+{
+    return create_dce<GenericModule>(dte, dev, netif);
+}
+
+std::unique_ptr<DCE<SIM7600>> create_SIM7600_dce_from_module(const std::shared_ptr<DTE>& dte, const std::shared_ptr<SIM7600>& dev, esp_netif_t *netif)
+{
+    return create_dce<SIM7600>(dte, dev, netif);
+}
+
+std::unique_ptr<DCE<SIM7600>> create_SIM7600_dce(const std::shared_ptr<DTE>& dte, esp_netif_t *netif, std::string &apn)
+{
+    auto pdp = std::make_unique<PdpContext>(apn);
+    auto dev = std::make_shared<SIM7600>(dte, std::move(pdp));
+
+    return create_dce<SIM7600>(dte, std::move(dev), netif);
+}
+
+
+//
+// C API definitions
+
+
+struct esp_modem_dce_wrap // need to mimic the polymorphic dispatch as CPP uses templated dispatch
+{
+    enum esp_modem_t { MODEM_SIM7600, MODEM_SIM800, MODEM_BG96 } modem_type;
+    void * dce_ptr;
+};
+
+static inline esp_err_t command_response_to_esp_err(command_result res)
+{
+    switch (res) {
+        case command_result::OK:
+            return ESP_OK;
+        case command_result::FAIL:
+            return ESP_FAIL;
+        case command_result::TIMEOUT:
+            return ESP_ERR_TIMEOUT;
+    }
+    return ESP_ERR_INVALID_ARG;
+}
+
+extern "C" esp_modem_t *esp_modem_new(const dte_config *config, esp_netif_t *netif, const char* apn)
+{
+    auto dce_wrap = new (std::nothrow) esp_modem_dce_wrap;
+    if (dce_wrap == nullptr)
+        return nullptr;
+    std::string apn_str(apn);
+    auto dte = create_uart_dte(config);
+    auto dce = create_SIM7600_dce(dte, netif, apn_str);
+    dce_wrap->modem_type = esp_modem_dce_wrap::MODEM_SIM7600;
+    dce_wrap->dce_ptr = dce.release();
+    return dce_wrap;
+}
+
+extern "C" void esp_modem_destroy(esp_modem_t * dce)
+{
+    assert(dce->modem_type == esp_modem_dce_wrap::MODEM_SIM7600);
+    auto dce_sim7600 = static_cast<DCE<SIM7600>*>(dce->dce_ptr);
+    delete dce_sim7600;
+    delete dce;
+}
+
+extern "C" esp_err_t esp_modem_read_pin(esp_modem_t * dce, bool &x)
+{
+    assert(dce->modem_type == esp_modem_dce_wrap::MODEM_SIM7600);
+    auto dce_sim7600 = static_cast<DCE<SIM7600>*>(dce->dce_ptr);
+    return command_response_to_esp_err(dce_sim7600->read_pin(x));
+}
+
+// define all commands manually, as we have to convert char* strings to CPP strings and references to
\ No newline at end of file
diff --git a/esp_modem/include/cxx_include/esp_modem_commands.hpp b/esp_modem/src/esp_modem_command_library.cpp
similarity index 65%
rename from esp_modem/include/cxx_include/esp_modem_commands.hpp
rename to esp_modem/src/esp_modem_command_library.cpp
index 5c928f0a8..51b419db4 100644
--- a/esp_modem/include/cxx_include/esp_modem_commands.hpp
+++ b/esp_modem/src/esp_modem_command_library.cpp
@@ -1,24 +1,18 @@
 //
-// Created by david on 3/2/21.
+// Created by david on 3/8/21.
 //
 
-#ifndef SIMPLE_CXX_CLIENT_ESP_MODEM_COMMANDS_HPP
-#define SIMPLE_CXX_CLIENT_ESP_MODEM_COMMANDS_HPP
-
-#include "esp_modem_dte.hpp"
-#include "esp_modem_dce_commands.hpp"
+#include "cxx_include/esp_modem_dte.hpp"
+#include "cxx_include/esp_modem_dce_module.hpp"
+#include "cxx_include/esp_modem_command_library.hpp"
 #include <string.h>
 
-enum class command_result;
-
-
-
+// TODO: Remove iostream
 #include <iostream>
 
-namespace esp_modem {
-namespace dce_commands {
+namespace esp_modem::dce_commands {
 
-template <typename T> static inline command_result generic_command(T t, const std::string& command,
+static inline command_result generic_command(CommandableIf* t, const std::string& command,
                                                                    const std::string& pass_phrase,
                                                                    const std::string& fail_phrase, uint32_t timeout_ms)
 {
@@ -35,16 +29,8 @@ template <typename T> static inline command_result generic_command(T t, const st
         return command_result::TIMEOUT;
     }, timeout_ms);
 }
-static inline void strip_cr_lf_tail(char *str, uint32_t len)
-{
-    if (str[len - 2] == '\r') {
-        str[len - 2] = '\0';
-    } else if (str[len - 1] == '\r') {
-        str[len - 1] = '\0';
-    }
-}
 
-template <typename T> static inline command_result generic_get_string(T t, const std::string& command, std::string& output, uint32_t timeout_ms)
+static inline command_result generic_get_string(CommandableIf* t, const std::string& command, std::string& output, uint32_t timeout_ms)
 {
     std::cout << command << std::endl;
     return t->command(command.c_str(), [&](uint8_t *data, size_t len) {
@@ -62,13 +48,7 @@ template <typename T> static inline command_result generic_get_string(T t, const
             } else if (token.find("ERROR") != std::string::npos) {
                 return command_result::FAIL;
             } else if (token.length() > 2) {
-//            response.resize(response.find('\r'));
-//            response.erase(std::find(response.begin(), response.end(), '\r'), response.end());
-//                std::cout << "|" << output << "|" << std::endl;
-//                const std::string& out(response);
-                output = token; //.substr(0,-1);
-                std::cout << "|" << token << "|" << std::endl;
-//                std::cout << output << std::endl;
+                output = token;
             }
             response = response.substr(pos+1);
         }
@@ -76,42 +56,42 @@ template <typename T> static inline command_result generic_get_string(T t, const
     }, timeout_ms);
 }
 
-template <typename T> static inline command_result generic_command_common(T t, std::string command)
+static inline command_result generic_command_common(CommandableIf* t, std::string command)
 {
     return generic_command(t, command, "OK", "ERROR", 500);
 }
 
 
-template <typename T> command_result sync(T t)
+command_result sync(CommandableIf* t)
 {
     return generic_command_common(t, "AT\r");
 }
 
-template <typename T> command_result set_echo(T t, bool on)
+command_result set_echo(CommandableIf* t, bool on)
 {
     if (on)
         return generic_command_common(t, "ATE1\r");
     return generic_command_common(t, "ATE0\r");
 }
 
-template <typename T> command_result set_pdp_context(T t, PdpContext& pdp)
+command_result set_pdp_context(CommandableIf* t, PdpContext& pdp)
 {
     std::string pdp_command = "AT+CGDCONT=" + std::to_string(pdp.context_id) +
                               ",\"" + pdp.protocol_type + "\",\"" + pdp.apn + "\"\r";
     return generic_command_common(t, pdp_command);
 }
 
-template <typename T> command_result set_data_mode(T t)
+command_result set_data_mode(CommandableIf* t)
 {
     return generic_command(t, "ATD*99##\r", "CONNECT", "ERROR", 5000);
 }
 
-template <typename T> command_result resume_data_mode(T t)
+command_result resume_data_mode(CommandableIf* t)
 {
     return generic_command(t, "ATO\r", "CONNECT", "ERROR", 5000);
 }
 
-template <typename T> command_result set_command_mode(T t)
+command_result set_command_mode(CommandableIf* t)
 {
     std::cout << "Sending +++" << std::endl;
     return t->command("+++", [&](uint8_t *data, size_t len) {
@@ -128,27 +108,27 @@ template <typename T> command_result set_command_mode(T t)
     }, 5000);
 }
 
-template <typename T> command_result get_imsi(T t, std::string& imsi_number)
+command_result get_imsi(CommandableIf* t, std::string& imsi_number)
 {
     return generic_get_string(t, "AT+CIMI\r", imsi_number, 5000);
 }
 
-template <typename T> command_result get_imei(T t, std::string& out)
+command_result get_imei(CommandableIf* t, std::string& out)
 {
     return generic_get_string(t, "AT+CGSN\r", out, 5000);
 }
 
-template <typename T> command_result get_module_name(T t, std::string& out)
+command_result get_module_name(CommandableIf* t, std::string& out)
 {
     return generic_get_string(t, "AT+CGMM\r", out, 5000);
 }
 
-template <typename T> command_result set_cmux(T t)
+command_result set_cmux(CommandableIf* t)
 {
     return generic_command_common(t, "AT+CMUX=0\r");
 }
 
-template <typename T> command_result read_pin(T t, bool& pin_ok)
+command_result read_pin(CommandableIf* t, bool& pin_ok)
 {
     std::cout << "Sending read_pin" << std::endl;
     return t->command("AT+CPIN?\r", [&](uint8_t *data, size_t len) {
@@ -167,15 +147,11 @@ template <typename T> command_result read_pin(T t, bool& pin_ok)
     }, 5000);
 }
 
-template <typename T> command_result set_pin(T t, const std::string& pin)
+command_result set_pin(CommandableIf* t, const std::string& pin)
 {
     std::cout << "Sending set_pin" << std::endl;
     std::string set_pin_command = "AT+CPIN=" + pin + "\r";
     return generic_command_common(t, set_pin_command);
 }
 
-} // dce_commands
-} // esp_modem
-
-
-#endif //SIMPLE_CXX_CLIENT_ESP_MODEM_COMMANDS_HPP
+} // esp_modem::dce_commands
\ No newline at end of file
diff --git a/esp_modem/src/esp_modem_dce.cpp b/esp_modem/src/esp_modem_dce.cpp
deleted file mode 100644
index 9efb60c2f..000000000
--- a/esp_modem/src/esp_modem_dce.cpp
+++ /dev/null
@@ -1,33 +0,0 @@
-#include "cxx_include/esp_modem_dte.hpp"
-#include "cxx_include/esp_modem_dce.hpp"
-#include <cstring>
-
-#include <utility>
-#include "esp_log.h"
-
-DCE::DCE(const std::shared_ptr<DTE>& dte, std::shared_ptr<DeviceIf> device, esp_netif_t * netif):
-        dce_dte(dte), device(std::move(device)), ppp_netif(dte, netif)
-{ }
-
-void DCE::exit_data() {
-    ppp_netif.stop();
-    device->set_mode(dte_mode::COMMAND_MODE);
-    uint8_t* data;
-    dce_dte->set_data_cb([&](size_t len) -> bool {
-        auto actual_len = dce_dte->read(&data, 64);
-        ESP_LOG_BUFFER_HEXDUMP("esp-modem: debug_data", data, actual_len, ESP_LOG_INFO);
-        return false;
-    });
-    ppp_netif.wait_until_ppp_exits();
-    dce_dte->set_data_cb(nullptr);
-    dce_dte->set_mode(dte_mode::COMMAND_MODE);
-}
-
-void DCE::set_cmux()
-{
-    device->set_mode(dte_mode::CMUX_MODE);
-    dce_dte->set_mode(dte_mode::CMUX_MODE);
-//    auto t = dce_dte->detach();
-//    auto cmux = std::make_unique<CMUXedTerminal>(std::move(t), dce_dte->get_buffer());
-//    dce_dte->attach(std::move(cmux));
-}
\ No newline at end of file
diff --git a/esp_modem/src/esp_modem_device.cpp b/esp_modem/src/esp_modem_device.cpp
deleted file mode 100644
index ad684d38d..000000000
--- a/esp_modem/src/esp_modem_device.cpp
+++ /dev/null
@@ -1,46 +0,0 @@
-//
-// Created by david on 3/3/21.
-//
-
-#include "cxx_include/esp_modem_dce_commands.hpp"
-#include "cxx_include/esp_modem_dte.hpp"
-
-#include "cxx_include/esp_modem_commands.hpp"
-
-
-
-bool Device::setup_data_mode() {
-    if (set_echo(false) != command_result::OK)
-        return false;
-    if (set_pdp_context(*pdp) != command_result::OK)
-        return false;
-//    if (set_data_mode() != command_result::OK)
-//        return false;
-    return true;
-}
-
-bool Device::set_mode(dte_mode mode) {
-    if (mode == dte_mode::DATA_MODE) {
-        if (set_data_mode() != command_result::OK)
-            return resume_data_mode() == command_result::OK;
-        return true;
-    } else if (mode == dte_mode::COMMAND_MODE) {
-        return set_command_mode() == command_result::OK;
-    } else if (mode == dte_mode::CMUX_MODE) {
-        return set_cmux() == command_result::OK;
-    }
-    return true;
-}
-
-
-command_result Device::set_echo(bool on) { return esp_modem::dce_commands::set_echo(dte, on); }
-command_result Device::set_data_mode() { return esp_modem::dce_commands::set_data_mode(dte); }
-command_result Device::resume_data_mode() { return esp_modem::dce_commands::resume_data_mode(dte); }
-command_result Device::set_pdp_context(PdpContext& pdp_context) { return esp_modem::dce_commands::set_pdp_context(dte.get(), pdp_context); }
-command_result Device::set_command_mode() { return esp_modem::dce_commands::set_command_mode(dte); }
-command_result Device::set_cmux() { return esp_modem::dce_commands::set_cmux(dte); }
-command_result Device::get_imsi(std::string& imsi_number) { return esp_modem::dce_commands::get_imsi(dte, imsi_number); }
-command_result Device::set_pin(const std::string& pin) { return esp_modem::dce_commands::set_pin(dte, pin); }
-command_result Device::read_pin(bool& pin_ok) { return esp_modem::dce_commands::read_pin(dte, pin_ok); }
-command_result Device::get_imei(std::string &imei) { return esp_modem::dce_commands::get_imei(dte, imei); }
-command_result Device::get_module_name(std::string &name) { return esp_modem::dce_commands::get_module_name(dte, name); }
diff --git a/esp_modem/src/esp_modem_device_factory.cpp b/esp_modem/src/esp_modem_device_factory.cpp
deleted file mode 100644
index 2fd49a573..000000000
--- a/esp_modem/src/esp_modem_device_factory.cpp
+++ /dev/null
@@ -1,10 +0,0 @@
-#include "cxx_include/esp_modem_dce_commands.hpp"
-#include "cxx_include/esp_modem_dte.hpp"
-
-//std::shared_ptr<DeviceIf> create_device(const std::shared_ptr<DTE>& dte, std::string &apn)
-std::shared_ptr<Device> create_device(const std::shared_ptr<DTE>& dte, std::string &apn)
-{
-    auto pdp = std::make_unique<PdpContext>(apn);
-    return std::make_shared<Device>(dte, std::move(pdp));
-}
-
diff --git a/esp_modem/src/esp_modem_dte.cpp b/esp_modem/src/esp_modem_dte.cpp
index 73a013467..2aa467df1 100644
--- a/esp_modem/src/esp_modem_dte.cpp
+++ b/esp_modem/src/esp_modem_dte.cpp
@@ -5,10 +5,11 @@
 DTE::DTE(std::unique_ptr<Terminal> terminal):
         buffer_size(DTE_BUFFER_SIZE), consumed(0),
         buffer(std::make_unique<uint8_t[]>(buffer_size)),
-        term(std::move(terminal)), mode(dte_mode::UNDEF) {}
+        term(std::move(terminal)), mode(modem_mode::UNDEF) {}
 
-command_result DTE::command(const std::string& command, got_line_cb got_line, uint32_t time_ms)
+command_result DTE::command(const std::string &command, got_line_cb got_line, uint32_t time_ms)
 {
+//    assert(term_id < term->max_virtual_terms());
     Scoped<Lock> l(lock);
     command_result res = command_result::TIMEOUT;
     term->write((uint8_t *)command.c_str(), command.length());
diff --git a/esp_modem/src/esp_modem_factory.cpp b/esp_modem/src/esp_modem_factory.cpp
new file mode 100644
index 000000000..e33a48158
--- /dev/null
+++ b/esp_modem/src/esp_modem_factory.cpp
@@ -0,0 +1,21 @@
+#include <functional>
+#include "cxx_include/esp_modem_types.hpp"
+#include "cxx_include/esp_modem_dte.hpp"
+#include "cxx_include/esp_modem_dce_module.hpp"
+
+template<typename T>
+std::shared_ptr<T> create_device(const std::shared_ptr<DTE>& dte, std::string &apn)
+{
+    auto pdp = std::make_unique<PdpContext>(apn);
+    return std::make_shared<T>(dte, std::move(pdp));
+}
+
+std::shared_ptr<GenericModule> create_generic_module(const std::shared_ptr<DTE>& dte, std::string &apn)
+{
+    return create_device<GenericModule>(dte, apn);
+}
+
+std::shared_ptr<SIM7600> create_SIM7600_module(const std::shared_ptr<DTE>& dte, std::string &apn)
+{
+    return create_device<SIM7600>(dte, apn);
+}
diff --git a/esp_modem/src/esp_modem_modules.cpp b/esp_modem/src/esp_modem_modules.cpp
new file mode 100644
index 000000000..5becd9e50
--- /dev/null
+++ b/esp_modem/src/esp_modem_modules.cpp
@@ -0,0 +1,23 @@
+//
+// Created by david on 3/8/21.
+//
+
+#include "cxx_include/esp_modem_dce_module.hpp"
+
+command_result SIM7600::get_module_name(std::string& name)
+{
+    name = "7600";
+    return command_result::OK;
+}
+
+command_result SIM800::get_module_name(std::string& name)
+{
+    name = "800L";
+    return command_result::OK;
+}
+
+command_result BG96::get_module_name(std::string& name)
+{
+    name = "BG96";
+    return command_result::OK;
+}
diff --git a/esp_modem/src/ppp_netif.cpp b/esp_modem/src/esp_modem_netif.cpp
similarity index 97%
rename from esp_modem/src/ppp_netif.cpp
rename to esp_modem/src/esp_modem_netif.cpp
index 407c70e35..a0ab9b331 100644
--- a/esp_modem/src/ppp_netif.cpp
+++ b/esp_modem/src/esp_modem_netif.cpp
@@ -5,15 +5,12 @@
 #include <utility>
 #include <esp_log.h>
 #include <esp_event.h>
-#include "cxx_include/ppp_netif.hpp"
+#include "cxx_include/esp_modem_netif.hpp"
 #include "cxx_include/esp_modem_dte.hpp"
 #include "esp_netif_ppp.h"
 
 #include <iostream>
 
-//struct ppp_netif_driver {
-//    esp_netif_driver_base_t base;
-//};
 
 void PPP::on_ppp_changed(void *arg, esp_event_base_t event_base,
                            int32_t event_id, void *event_data)
diff --git a/esp_modem/src/esp_modem_uart.cpp b/esp_modem/src/esp_modem_uart.cpp
index 6c497e523..743bb1800 100644
--- a/esp_modem/src/esp_modem_uart.cpp
+++ b/esp_modem/src/esp_modem_uart.cpp
@@ -177,11 +177,8 @@ std::unique_ptr<Terminal> create_uart_terminal(const dte_config *config)
         ESP_LOGE(TAG, "%s", e.what());
         return nullptr;
     }
-
 }
 
-
-
 void uart_terminal::task()
 {
     std::function<bool(size_t len)> on_data_priv = nullptr;