Wire: fix "Arduino way" I2C scan

facchinm · facchinm · commit da21f0e4987a · 2021-05-04T15:02:37.000+02:00
diff --git a/libraries/Wire/Wire.cpp b/libraries/Wire/Wire.cpp
@@ -67,6 +67,14 @@ void arduino::MbedI2C::beginTransmission(uint8_t address) {
 }
 
 uint8_t arduino::MbedI2C::endTransmission(bool stopBit) {
+	#ifndef TARGET_PORTENTA_H7
+	if (usedTxBuffer == 0) {
+		// we are scanning, return 0 if the addresed device responds with an ACK
+		char buf[1];
+		int ret = master->read(_address, buf, 1, !stopBit);
+		return ret;
+	}
+	#endif
 	if (master->write(_address, (const char *) txBuffer, usedTxBuffer, !stopBit) == 0) return 0;
 	return 2;
 }

Original file line number	Diff line number	Diff line change
`@@ -67,6 +67,14 @@ void arduino::MbedI2C::beginTransmission(uint8_t address) {`
`67`	`67`	`}`
`68`	`68`
`69`	`69`	`uint8_t arduino::MbedI2C::endTransmission(bool stopBit) {`
	`70`	`+ #ifndef TARGET_PORTENTA_H7`
	`71`	`+ if (usedTxBuffer == 0) {`
	`72`	`+ // we are scanning, return 0 if the addresed device responds with an ACK`
	`73`	`+ char buf[1];`
	`74`	`+ int ret = master->read(_address, buf, 1, !stopBit);`
	`75`	`+ return ret;`
	`76`	`+ }`
	`77`	`+ #endif`
`70`	`78`	`if (master->write(_address, (const char *) txBuffer, usedTxBuffer, !stopBit) == 0) return 0;`
`71`	`79`	`return 2;`
`72`	`80`	`}`