From a25ccb2ef7893d7f9a33b16a63fb72f996051eea Mon Sep 17 00:00:00 2001
From: me-no-dev <hristo@espressif.com>
Date: Tue, 17 Nov 2020 02:30:12 +0200
Subject: [PATCH] Fix Wire.begin causing divide by zero

Fixes: https://github.com/espressif/arduino-esp32/issues/4530
---
 cores/esp32/esp32-hal-i2c.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/cores/esp32/esp32-hal-i2c.c b/cores/esp32/esp32-hal-i2c.c
index cfc620f2..df9eace7 100644
--- a/cores/esp32/esp32-hal-i2c.c
+++ b/cores/esp32/esp32-hal-i2c.c
@@ -1798,6 +1798,10 @@ i2c_t * i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t clk_speed){
 	if(i2c_num >= 2){
 		return NULL;
 	}
+	if(!clk_speed){
+	    //originally does not change the speed, but getFrequency and setFrequency need to be implemented first.
+	    clk_speed = 100000;
+	}
 	i2c_t * out = NULL;
 	if(i2c_ports[i2c_num] == NULL){
 		out = (i2c_t*)malloc(sizeof(i2c_t));