Error -Verification error - 0x42 transmitted but nothing received at byte 0


New Member
Started getting this while testing a 20M2 in a circuit and trying to download a new program. Program was in an endless loop. There is no answer out in Google other than power supply issues or miss-wired. I resolved the issue by turning off circuit power, starting the download via USB cable and then immediately turning on circuit power. Hopefully this will help someone else.


Technical Support
Staff member
Welcome to the PICAXE Forum.

What you describe is more commonly referred to as a Hard Reset procedure. When the PICAXE is busy, waiting for input, sleeping, and so on, it can miss the download activation from the programming software.

Normally this will manifest itself as a "hardware not found" error because nothing is seen from the PICAXE, but where a PICAXE may be sending data to a Terminal, using DEBUG, even toggling I/O lines, it can be that this is mistaken as a download acknowledgement, but that then never completes.

Turning the PICAXE off, initiating the download, and then powering up the PICAXE should cause it to always see the download initiation and respond to it as expected. As appears to be the case here and we are glad to hear you solved your problem.