adc_timer_dma and Adafruit SSD1306_128x32_i2c reboot loop

[NoRez4U]

Hello All,

I've run across a problem when combining the two sample programs listed in the title. Individually, the sample programs work as expected. Once combined, the Teensy 4.1 goes into a reboot loop (I suspect) when it tries to write to the OLED over i2c.

CrashReport is as follows:
CrashReport: A problem occurred at (system time) 13:35:3 Code was executing from address 0x10E7A CFSR: 82 (DACCVIOL) Data Access Violation (MMARVALID) Accessed Address: 0x0 (nullptr) Check code at 0x10E7A - very likely a bug! Run "addr2line -e mysketch.ino.elf 0x10E7A" for filename & line number. Temperature inside the chip was 49.71 °C Startup CPU clock speed is 600MHz Reboot was caused by auto reboot after fault or bad interrupt detected

Unfortunately, running "add2line..." produces nothing useful.
`C:\Users\manda\AppData\Local\Temp\arduino_build_885234>"C:\Program Files\arduino-1.8.19\hardware\tools\arm\bin\arm-none-eabi-addr2line.exe" -e aMon.ino.elf 0x10E7A

??:?`

[NoRez4U]

This ended up not being a bug. It was the lack of a display.begin() before calling the SSD1306 device to display some text. The sample Adafruit code was missing it. I will post to their forums regarding the need for the call. Thank you.