Linards Ticmanis wrote:
Michael J. Mahon wrote:Linards Ticmanis wrote:(The next flakey card is a Videx clone now. It tends to get about 1% of characters wrong. This one doesn't seem to be software based as it happens even without anything booted).Odd. The problem could be in the transfer to the card (likely if the errors are "stable"), or in the card's SRAM (pretty unusual).Must be in the transfer, because once a wrong character is on screen, it lives on, even through scrolling. I'll try replacing some of the 74LSxx when I get time and money again.
And be sure to check the "fingers" and slot socket, too, particularly D3-D7. -michael Music synthesis for 8-bit Apple II's! Home page: http://members.aol.com/MJMahon/ "The wastebasket is our most important design tool--and it is seriously underused."