I've now added an all through-hole version of the TANDY 600 ram card,
because why not? There's even room for sockets and the BOM includes
them. https://github.com/bkw777/TANDY_600_RAM
Also changed to a simpler circuit that uses just 3 AND gates instead of
an 8:3 encoder. The new idea isn't proven yet but I have already ordered
pcbs to test.
I have received pcbs of my initial tiny version that still used a 74148
just in the tiny pcb, but I'm not even going to build one now. But it is
comical seeing that tiny pcb next to the original official ram card. The
new pcb is entirely within the footprint of just the *connector*.
https://photos.app.goo.gl/Lm2r2ftutK75Xy9K8
(newest at the bottom)
And I'm now working on yet a different idea that dispenses with the
special $6 Eurocard connector and supplies both banks from a single ram
chip on a single pcb that just lays across both connectors and uses only
plain vertical male pins. That will be the simplest and cheapest way to
max out a 600.
So for multiple reasons don't rush to order anything yet.
That said, the current pcbway and oshpark links are still the tested
previous version and it's safe to order that if you don't want to wait.
It works and there is no reason not to use it. The new versions won't
work any better.
--
bkw
