Random STuff

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DoG
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Joined: Sat Apr 07, 2018 12:26 pm

Re: Random STuff

Post by DoG »

UPDATE
  1. Got a H4 #2 to solder up. I have the board but haven't order any parts for it yet. Don't have a spare shifter and they are quite impossible to find. So this will probably be a board for the new HDMI board in developing stages.

    I have a shifter now thanks to Exxos got some in his store.

  2. Doing a Alt-RAM board with 256Kb ROM switcher on it. Schematics and board has been done. 5 PCB is being made. Parts has been ordered.

    PCB has arrived. Not seen the board yet though. I am at my cottage now and the pcb is at home in the flat. In the post box.

  3. Mega-ST IDE board. Same as rubber_jonnie has done. Made a few changes to the board design. I have soldered one board and have 4 more. I have not burnt the GAL for it yet though. Don't have a Mega or the GAL burner here in the flat. Probably use this with a 27C4001/27C040 and a small board I got some time ago to switch between 4 different ROMs.

    Desoldered a IDE/SD board I have and solder in some female pin header instead. Burnt a GAL. Built up two 28 to 32 pin ROM adapter so I can use it for random chips. Burnt TOS 2.06 and TOS 1.04 (with bootable IDE driver) and tried it out. Works great. Installed it in a Mega ST1.
    IDE_SD_desolder.jpg
    IDE_SD_desolder.jpg (69.42 KiB) Viewed 5665 times
    28to32pin.jpg
    28to32pin.jpg (86.54 KiB) Viewed 5665 times
    IDEand206decoderBoard.jpg
    IDEand206decoderBoard.jpg (77.17 KiB) Viewed 5665 times
    MegaSTwithIDEandTOS206.jpg
    MegaSTwithIDEandTOS206.jpg (215.1 KiB) Viewed 5665 times



  4. Get the PAK68/3-030 to 50MHz. Now at 40 MHz. Need to get hold of FRAK, PuPla or perhaps PCB for or doing board myself. Seems a long way to go.

    I might have a PuPla2 and a FRAK board soon. The deal haven't been made yet since shipment in Corona time thru the world/Europe is a bit troublesome. The PuPla is already built but the FRAK is just the PCB so need to order components for that after the deal is done.

  5. Solder up a IDE-PCB R1C v1.1 i got from exxos. I have the parts for this.

    Yes, this is done. Not tested. I haven't got an adapter for 40/44pin IDE or a SD/CF-IDE board with 44pin. I think I have at home in the flat. I might have here. I have to check.
    IDE_R1C_11.jpg
    IDE_R1C_11.jpg (106.23 KiB) Viewed 5665 times
    IDE_R1C_11_fixes.jpg
    IDE_R1C_11_fixes.jpg (91.44 KiB) Viewed 5665 times

Oh yeah, I have modded my UV eraser I got from china some time ago. I hated the noise it made with that mechanical knob/handle. Bought a timer board and some buttons. It even remember the time when unplugged so I don't need to set that every time. Looks like shit inside.
EPROM_UVeraser.jpg
EPROM_UVeraser.jpg (57.53 KiB) Viewed 5665 times
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DoG
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Re: Random STuff

Post by DoG »

Fixed a STfm board. Sockets on everything. Almost. Changed resistor arrays on data/address bus and 10k resistor array on the WD1772 also. Did a 2 chip conversion by adding the 74LS11 and some solder blobs changing.

But had some troubles and had to check some solder spots since I didn't get it started. Noticed that I had got som solder blobs shorts when using a solder sucker. God I hate those.

Managed to put one of TOS 1.02 chips upside down and got white screen of course on boot. Diag cart didn't work either. Didn't find that problem for a while. Kind of obvious when you do find it:
TOaSt.jpg
TOaSt.jpg (81.42 KiB) Viewed 5602 times
I happened to do this with a TOS 1.02 german language before and the worked fine so I guess it it just luck if it survives. Those to in the pic is in the garbage now.

Well that boards finally running now.
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DoG
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Re: Random STuff

Post by DoG »

Did a recap on a SR98 PSU for the board above. My keyboard that I fixed is being used with the board above. Need a case for it. Actually need two cases. One for my H4 #2 as well.

Did a transplant meanwell PSU on a MegaST PSU plate for my second Mega ST.

I have ordered some new caps to change them all on both the Mega main board.

I have made schematics for the MV16 cartridge and made a new SMT clone of it. Half as big as the original. So that PCB is on it's way from china.
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DoG
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Re: Random STuff

Post by DoG »

Got some PCB from china. Did the rom decoder board @Smonson linked to in this post. Also got the ROM adapter PCB inspired by Martin Šoltés 32 to 28pin adapter. Tried it out in a Mega 1. Worked right away.

Decoder board pic.jpg
Decoder board pic.jpg (41.41 KiB) Viewed 5477 times
ROM adapter pic.jpg
ROM adapter pic.jpg (61.24 KiB) Viewed 5477 times
Installed Mega 1 pic.jpg
Installed Mega 1 pic.jpg (222.85 KiB) Viewed 5477 times
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JezC
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Re: Random STuff

Post by JezC »

:bravo: :coolpics: :goodpost:

Sweet!
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agranlund
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Re: Random STuff

Post by agranlund »

Nice! :dualthumbup:
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DoG
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Re: Random STuff

Post by DoG »

Had bought some 29C010 in TSOP32 package some time ago. So made a adapter PCB for it to fit a DIP28 and also got that in the recent shipment from the PCB manufacturer. Burnt TOS 2.06 on the 29C010 chip and solder up a set and it worked great with the previous ROM decoder board. Will do some test with 29C020 (and maybe 29C040 later on) to get EmuTOS and TOS 2.06 with just a flip of a switch.

TSOP32 board solder stages pic.jpg
TSOP32 board solder stages pic.jpg (54.67 KiB) Viewed 5449 times
Mega 1 with 29C010 pic.jpg
Mega 1 with 29C010 pic.jpg (231.81 KiB) Viewed 5449 times
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PhilC
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Re: Random STuff

Post by PhilC »

@DoG interesring choice of eprom, what speed are they?
If it ain't broke, test it to Destruction.
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DoG
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Re: Random STuff

Post by DoG »

PhilC wrote: Thu Jul 09, 2020 8:11 pm @DoG interesring choice of eprom, what speed are they?
70ns
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PhilC
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Re: Random STuff

Post by PhilC »

Looks like a very good solution for Mega and STFMs
If it ain't broke, test it to Destruction.
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