Add i2c_read_register function.

nixpulvis · Oct 11, 2015 · ebad4e1 · ebad4e1
1 parent 633ed7b
commit ebad4e1
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diff --git a/lib/avrm/i2c.c b/lib/avrm/i2c.c
@@ -52,6 +52,18 @@ void i2c_write(byte data){
   return;
 }
 
+int i2c_read_register(byte addr, byte rgstr, byte *buf, size_t len)
+{
+  i2c_start(addr, I2C_WRITE);
+  i2c_write(rgstr);
+  i2c_start(addr, I2C_READ);
+  for (int i = 0; i < len; i++)
+    buf[i] = i2c_read_ack();
+
+  // TODO: Errors?
+  return 0;
+}
+
 byte i2c_read_ack(void){
   // start TWI module and acknowledge data after reception
   TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWEA);

diff --git a/lib/avrm/i2c.h b/lib/avrm/i2c.h
@@ -24,6 +24,9 @@ byte i2c_start(byte address, byte config);
 // i2c_write
 void i2c_write(byte data);
 
+// i2c_read_address
+int i2c_read_register(byte address, byte register, byte *buffer, size_t length);
+
 // i2c_read_ack
 byte i2c_read_ack(void);