exxos's Atari, Amiga & retro forum

• Board built without blitter and using Exxos Ram Board with a 4MB SIMM installed.
• Modifications installed so far https://www.exxosforum.co.uk/forum/viewtopic.php?f=19:
  • Jumper Pads - SJ1 - 5 all linked (soldered)
  • Reset Fix - R920 leg moved to be soldered to diode, tracks cut and patch wire in place
  • Hsync Fix - Pin 8 leg removed from U51 socket and Pin 8 and 9 on underside of board soldered together
• Using the scope on the GLUE the board is producing 15.6kHz and 50Hz out. For the 50Hz it is initially 60Hz then immediately goes to 50Hz
• On every switch on or reset I get a full white screen that turns to black screen with white border. Sometimes it stays solid but more than often it starts scrolling horizontally.

exxos wrote: 18 Sep 2018 15:21 I would first double check continuity on the ROM socket first of all.. socket problems are pretty common :(

Sounds like your getting some TOS init at least, it must be setting the palette to get a full white screen.. but never seen it go black after that..

Also please check BERR on the CPU...

Icky wrote: 18 Sep 2018 17:22 BERR on CPU goes high 5v at start and stays there

exxos wrote: 18 Sep 2018 17:33 What about BG, BGACK, BR ? All those should stay high all the time...

Icky wrote: 18 Sep 2018 18:00 BG and BGACK are high all the time but BR is low all the time

exxos wrote: 18 Sep 2018 18:12 OK.. "bodge wire 1" time...

Icky wrote: 18 Sep 2018 18:13 OK - Lets give it a go