When I built an original REX I had a similar problem turned out there was a bad solder joint on the CPLD. The soldering looked fine from a visual inspection but when I used my dental pick to check each joint one of the pins moved. Fixed the bad joint and the board worked fine. Might be worth a quick check to eliminate that possibility.
Another issue I had was poor contact in the OPT ROM socket. I had done a bad job on the grinding stage and left a slight angle on the edge which meant it worked if I pushed it into the socket but would not work when released. Turns out the contact with the socket was not very good. Did a slight regrind and it worked without my thumb for support. From: M100 <m100-boun...@lists.bitchin100.com<mailto:m100-boun...@lists.bitchin100.com>> on behalf of Brian Brindle <bbrin...@gmail.com<mailto:bbrin...@gmail.com>> Reply-To: <m...@bitchin100.com<mailto:m...@bitchin100.com>> Date: Thursday, October 19, 2017 at 10:22 AM To: <m...@bitchin100.com<mailto:m...@bitchin100.com>> Cc: Model 100 Discussion <m100@lists.bitchin100.com<mailto:m100@lists.bitchin100.com>> Subject: Re: [M100] REX Castellated board I have one put together that programmed up OK but am having issues getting the REX software on it. It erases all the blocks just fine but hangs when re-loading to block 0. Probably something up with the flash.. I'll report back when I have more info. Brian On Thu, Oct 19, 2017 at 7:25 AM, Stephen Adolph <twospru...@gmail.com<mailto:twospru...@gmail.com>> wrote: Has anyone made a REX successfully with that modified PCB yet? I would like to know if that artwork is good or bad. ..Steve
