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rambo / TinyWire

My modifications to TinyWire Arduino libs
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Setting Slave Address over 0x3F #41

Open patrickpoirier51 opened 6 years ago

patrickpoirier51 commented 6 years ago

I can get stable reading when Slave Address is < 0x40 with this code void setup() { pinMode(Rx, INPUT); pinMode(Tx, OUTPUT); mySerial.begin(9600); TinyWireS.begin(I2C_SLAVE_ADDR); TinyWireS.onRequest(requestEvent); } void requestEvent() {
SendCount++; //increment this switch (SendCount) { case 1: sendByte = distLow; break; case 2: sendByte = distHigh; SendCount=0; break; } TinyWireS.send(sendByte); }

When Address is => 0x40 , its spitting garbage.

Wild guess: Seems to be an issue with the write bit being the 7th bit (instead of 8)

rambo commented 6 years ago

The write bit is not the issue, but I think I've heard of this problem before but never had any time to really look into it.

anderstogern commented 5 years ago

Hi there and thanks for this great library!

I can confirm this issue.

For a long period of time (about a year) I have been able to successfully use slave address 0x50 for a slave that only returned a single byte of data and did not receive anything (no receiveEvent defined).

Recently, I had the need to change the slave to return 3 bytes and receive a single byte. Changing the code broke the communication and it was only after several nights of frustration that I discovered this issue and gave changing the address (to 0x20) a try, which immediately fixed the problem.

For good measure, the slave is an AtTiny84 and the master an Adafruit Huzzah ESP8266 (not the Feather one).

Cheers!