Sporniket's log on hardware stuff

[Darklord]

That is Bruce from B&C Computervisions.

I've bought several things from him in the past and it's almost
always been a good experience.

For some reason, in my poor addled brain, I was thinking the
TeamTap was rare.

I might be confusing it with ICD's Catbox or something.

Who knows - too many Atari memories bouncing around in my
head, competing for notice?

[Darklord]

Wow. I even found -1- on Amazon.

https://www.amazon.com/Atari-Jaguar-Team-Tap/dp/B000YBERNQ

Oh forgot... Guess we can't post Amazon links?

[sporniket]

Just after getting my refund for the Atari 520ST, I could not help buying this tattered mega st, for not too much. Now I have to postpone trying getting my hand on a 520ST (or just a motherboard), but I am ready for when I will want to convert the schematics of the Mega ST, likely in two years (because, I plan finish the 520ST this year, then do the STF next year)

2023-04-03--00-mega-st-overview.jpg (129.88 KiB) Viewed 1616 times

2023-04-03--01-scratched.jpg (190.57 KiB) Viewed 1616 times

2023-04-03--02-burned.jpg (199.84 KiB) Viewed 1616 times

[Darklord]

The Mega's are great machines. It's a Mega ST4 (with lots of upgrades) that I use to
run my BBS.

You'll have lots of fun rehabilitating that machine.

[sporniket]

I got some time that I allocated to get some progress on my 520ST schematic conversion, so I went on with the CPU and the reset circuit. The wiring of the resistor networks was a PITA (sometimes I see a pin #10 on a 9-pins resistor network).

So this is a provisional work until I can check on real hardware. And I will move on with the schematics and do the PCB afterwards when all is done, as alternating between both turned out less efficient as I believed at first.

subsheet_105--U36-37-Reset-circuit.png (440.23 KiB) Viewed 1504 times

[sporniket]

Starting to convert the last sheet, starting with the MFP and the serial port. It was done quite quickly, and the whole fit on one A4 sheet.

subsheet_100-U11–68901 ; U13–14 J4–RS-232 port.png (331.94 KiB) Viewed 1453 times

[sporniket]

Today a first ACIA with the keyboard and joystick/mouse ports. By the way, please enlighten me, what is the "keyway" ???

subsheet_101_U21-Acia ; J10-11-12-Joystick, mouse, keyboard ports.png (285.22 KiB) Viewed 1421 times

[exxos]

Keyway pin 2 ?

Capture.PNG (122.96 KiB) Viewed 1420 times

[sporniket]

Yes I am not sure. Why name an unconnected pin, and on the other hand, the latest wire to pin 17 (that goes through all the other wire) is unnamed ?

I have the answer, on the schematic of the keyboard

Capture d’écran du 2023-04-19 21-26-17.png (36.21 KiB) Viewed 1417 times

And then I have the "Eureka" moment : it must be the polarisation of the connector, to not plug it in the wrong orientation ?

[exxos]

And then I have the "Eureka" moment : it must be the polarisation of the connector, to not plug it in the wrong orientation ?

Yep. "Missing pin" basically. Atari just called it "KEYWAY" or "KEY" it seems.

If you look at one of the motherboards...

IMG_3359.JPG (415.86 KiB) Viewed 1416 times

... You can see the missing pin.