Weird bug in SD card code

Frank van den Hoef, who is adapting the Steckschwein SPI & FAT32 code for his tiny65 machine made me aware of a classic mistake for a 6502 assembly coder to make. Namely in our sdcard driver, when waiting for the “proper” response from the card (which should have bit 7 cleared). The routine handling this looked like this: 1 sd_cmd_response_wait: 2 ldy #sd_cmd_response_retries 3 @l: dey 4 beq sd_block_cmd_timeout ; y already 0?