Populated PCB with fix for unneeded inverter

 

Lots of progress but little time to talk about it.

Here’s the fully populated card installed.  There were two issues identified so far with the PCB design.  One, the battery holder silkscreen was upside down.  The second fix involved an inverter that needed removed whenever we decided to migrates from a flip-flop(74LS74) design to a SR NAND latch made out of NAND(74LS00) gates.

The memory tests are passing at 100% now!@#

However, there is still a minor issue with how the card responds on bootup, and I’m investigating!

newpcb_installed