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Re: Random STuff

Posted: 01 Jan 2021 01:18
by DoG
Fixing the PCB at least. Then I have to see what I order...

Fixing_it.png

Re: Random STuff

Posted: 03 Jan 2021 16:33
by DoG
Trying to fix a floppy disc drive I have and took some photo of it in mid november. Now that I have bought the part and doing some work on it, but now I can't find the plastic front and eject button anywhere. I have searched all over. I had it put together so that I didn't loose any parts... I think. I can't remember if I didn't assemble it all the way the last time or if I have lost it this time.

I have clearly lost my marbles, that's for sure.

Re: Random STuff

Posted: 03 Jan 2021 16:57
by PhilC
DoG wrote: 03 Jan 2021 16:33
I have clearly lost my marbles, that's for sure.
JOIN THE CLUB :dizzy:

Re: Random STuff

Posted: 08 Jan 2021 17:07
by DoG
Tested Hatari in 060 mode. 32MHz though. Funny GemBench results against a 68k. :D

ridiculous.png

Re: Random STuff

Posted: 09 Jan 2021 22:58
by DoG
Soldered up a Stereo Master Cartridge. Old 8-bit sampling cart. Not really for practical use in today's age. But fun little project nevertheless. Tried it out and it works at least. More info at Atari Mania.

2021-01-09 14.55.00.jpg

Re: Random STuff

Posted: 23 Jan 2021 21:18
by DoG
Finally soldered up the 8Mb attachment board for the ST Ram in the TT. Didn't work the first time. Thought it needed beefier VCC and GND so tried that and also found that I had forgotten to solder 1 pin. So test was with the thick cables in place but that was removed later on since it wasn't needed. Ran YARTT for 4h or something like that.

ST 8Mb Ram 2.jpg
8Mb test.jpg

Re: Random STuff

Posted: 17 Mar 2021 20:17
by DoG
So I got me another Mega pretty cheap. A two megger. Tried it out and it is working. So a good start. So this is the board I am going to do some work on.

Before.jpg

Since keyboard isn't always going to be attached and I hate to hear the frequent beeps that happens if you don't, I tied the 10K resistor on the Rx line to 5V instead of ground.

Clicketyclick off.jpg

Desoldered the floppy cable and soldered in a IDC 34 pin connector.

Desoldered floppy cable.jpg

Removed the six german roms and used my 32-28 pin pcb to use two 27C010. Soldered in pin headers on W2, W3 and W4. But it didn't work for some reason. Found out that previous owner had cut a pin on U12. So new chip and it worked.

74LS11 pin 12 cut.jpg

I had some pcb made to get the ram up to 4Mb (the blue one). Silkscreen is a bit wrong and I forgot to ground 1 pin but tried the board out anyway with some modifications. New pcb is on its way from China. So will use 8 of these boards later. Soldered up a flip-connector pcb for the gotek.

Ram, rom, floppy flip pcb fixed.jpg

The small blitter fix board needs to go. Checked that I got a blitter that doesn't need the fix board. Fixed the severed track underneath the motherboard and use some green nail polish over it.

Blitter pcb remove fix under MB.jpg
Nail-polish applied 2 times.jpg

The 68k processor ( A Toshiba. Nice) was desoldered and a socket was soldered in its place.
68k socket.jpg

Re: Random STuff

Posted: 17 Mar 2021 20:58
by DoG
Soldered up a RGB2HDMI unit and tried on previous Mega ST2. Didn't work. Had no v sync. Don't know why. I have to investigate that later. But it worked fantastic on my H5 B1.

RGB2HDMI top.jpg
RGB2HDMI bottom.jpg

Re: Random STuff

Posted: 04 Apr 2021 09:59
by DoG
Desoldered the cables for the battery and put a header there instead so it is detachable.

Battery pins 1.jpg



Got my new RAM PCBs. Got the idea from Lynxman at Atari-home.de. For some reason I only ordered 5 but need 8 so the rest is on the way from China now. Forgot to soldered in the resistors for RAS2, CAS2L and CAS2H so it didn't work at first. But now all is up and running. Did 10K pull-ups on DMA/WD1772 lines and 1K pull-ups on the 74LS06 for the floppy. These are just two PCBs and can easily be removed.

RAM 4x1 soldered.jpg
RAM installed, DMA pull-up and floppy pull-up.jpg

Re: Random STuff

Posted: 11 Apr 2021 19:00
by DoG
Finished my ACSI2CF PCB. Ran XFERRATE on a STe with TOS v1.06, 4Mb. Pretty nice speed:

xferrate ACSICF.jpg