MCUdude / MightyCore

Arduino hardware package for ATmega1284, ATmega644, ATmega324, ATmega324PB, ATmega164, ATmega32, ATmega16 and ATmega8535
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Don't waste RAM in the low-level TWI Wire drivers. #263

Closed dewhisna closed 1 year ago

dewhisna commented 1 year ago

Apply MCUdude/MiniCore#245 to this MightyCore repo.

Since twi_readFrom() and twi_writeTo() are both blocking functions, there is no need to allocate a special twi_masterBuffer. Doing so wastes valuable RAM, uses extra time to copy the data to the secondary buffer, and limits the transfer size to TWI_BUFFER_SIZE. Instead, it only needs a pointer to the buffer for the IRQ to use for the transfer. And, if asynchronous non-blocking functions are ever added, which will require a different API and callbacks, etc., then the existing txBuffer and rxBuffer for slave mode can just be used there too, since master mode and slave mode can't both be active at the same time.

MCUdude commented 1 year ago

Thank you!