Closed as not planned
Description
Description
#include <Wire.h>
long lastms;
volatile int x = 0;
volatile int y = 0;
#define STM
void receiveEvent(int howMany) {
x = Wire.read();
}
void requestEvent() {
y = 1;
}
void setup() {
Serial.begin(115200);
#ifdef STM
//STM32F103
pinMode(PB6, INPUT); //PB6=SCL
pinMode(PB7, INPUT); //PB7=SDA
Wire.setSCL(PB6);
Wire.setSDA(PB7);
#elif
//Arduino Nano
pinMode(A4, INPUT);
pinMode(A5, INPUT);
//Wire.setSDA(A4);
//Wire.setSCL(A5);
#endif
Wire.begin(11); // join i2c bus as slave
//Wire.onRequest(requestEvent);
Wire.onReceive(receiveEvent);
lastms = millis();
}
void loop() {
if (millis() > lastms + 1000) {
Serial.print("-");
lastms = millis();
}
if (x != 0) {
Serial.print("U:0x");
Serial.println(x, HEX);
x = 0;
}
if (y != 0) {
Serial.println("V");
y = 0;
}
}
Environment
-
Boards platform name: Bluepill / own board / Arduino Nano (Nano and Leonardo works fine)
-
Boards platform version (as shown in Boards Manager):
-
ArduinoCore-API version (if you manually installed it):
Current behavior
If compiled for Nano, the application works. (displaying the incoming I2C requests.)
When compiled for STM32F103 - with CDC serial, it does not. (it outputs only the "-" each 1sec.)
The incoming data is at the same time decoded by an oscilloscope, so pullups etc are ok.
Expected behavior
I expect the code to work on STM32F103C8 /Bluepill like it did on Nano
Additional information
On incoming I2C data, PB6 (SCK) is being pulled low, and held low by the controller, effectively killing all further traffic.
This happens even if USB /Serial support is set to NONE