From 7abb15ca6277d4fb7645a4c90641d4d40109a191 Mon Sep 17 00:00:00 2001
From: me-no-dev <hristo@espressif.com>
Date: Thu, 17 Nov 2016 00:46:56 +0200
Subject: [PATCH] reset i2c cmd buffer before read/write

related to [issue
53](https://github.com/espressif/arduino-esp32/issues/53)
---
 cores/esp32/esp32-hal-i2c.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/cores/esp32/esp32-hal-i2c.c b/cores/esp32/esp32-hal-i2c.c
index d845bc09..fefd761a 100644
--- a/cores/esp32/esp32-hal-i2c.c
+++ b/cores/esp32/esp32-hal-i2c.c
@@ -112,6 +112,13 @@ void i2cSetCmd(i2c_t * i2c, uint8_t index, uint8_t op_code, uint8_t byte_num, bo
     i2c->dev->command[index].op_code = op_code;
 }
 
+void i2cResetCmd(i2c_t * i2c){
+    int i;
+    for(i=0;i<16;i++){
+        i2c->dev->command[i].val = 0;
+    }
+}
+
 void i2cResetFiFo(i2c_t * i2c)
 {
     i2c->dev->fifo_conf.tx_fifo_rst = 1;
@@ -138,6 +145,7 @@ i2c_err_t i2cWrite(i2c_t * i2c, uint16_t address, bool addr_10bit, uint8_t * dat
         uint8_t dataSend = willSend;
 
         i2cResetFiFo(i2c);
+        i2cResetCmd(i2c);
 
         //CMD START
         i2cSetCmd(i2c, 0, I2C_CMD_RSTART, 0, false, false, false);
@@ -222,6 +230,7 @@ i2c_err_t i2cRead(i2c_t * i2c, uint16_t address, bool addr_10bit, uint8_t * data
     I2C_MUTEX_LOCK();
 
     i2cResetFiFo(i2c);
+    i2cResetCmd(i2c);
 
     //CMD START
     i2cSetCmd(i2c, 0, I2C_CMD_RSTART, 0, false, false, false);