For those of you who might not get the significance, workbench loads a number of libraries into the extended fast memory on bootup. As you can see in this image below, more fast memory is actually being used than the...
Amiga A501 Replacement
RTC Progress
RTC appears to be working and keeping the date and time across cold-starts. I picked the Epson RTC-72423 which is about a $6 chip, but is obviously directly compatible with the OKI Semiconductor MSM6242B. The design...
Found potential race condition on writes
After looking at datasheets for the 273 latches used and 74act74 flipflop used, the worst case propagation delay is something like 12.3ns. But my NAND gate ACT00 logic which is triggered by the same CAS signals has a...
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...
PCBs have arrived!
Just in time for Christmas, the PCBs have arrived from China. I used Seeed Studio (Fusion PCB Service) and they look pretty good. Here’s the first look at them. I’m just about to solder one up, so wish me...
PCB ordered from Seeed Studio
I placed the order late last night for the PCB! The PCB design is obviously finished, fully passes the kicad DRC checks, the problems with the footprints were solved. I’ve decided to go with Seeed Studio’s...
