Year: 2022

I have been observing rhythm patterns being corrupted intermittently while I develop the firmware of the 909 clone. I first thought it is due to some bug in my firmware, but the occurrences are too random for it. I started thinking that it is some hardware problem in the processor, so looked this issue closely. I noticed that the corruptions happen only when I power cycle the processor. It’s a good clue. I searched around to know what this problem is and how to prevent it.

The TR-909 clone firmware I’m currently developing writes sequence patterns to eeprom. The avr-libc library provides eeprom writing function, but it is synchronous.

https://www.nongnu.org/avr-libc/user-manual/group__avr__eeprom.html

However, many of the real-time processing in the firmware are done without interrupts, then these processes stall during the slow (synchronous) function. So I decided to develop the asynchronous version of eeprom writing function by my own.