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SukkoPera / OpenKickstartSwitcher

Open Hardware Kickstart Switcher for Amiga Computers
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Mechanical incompatibility between OpenKickstartSwitcher and OpenAmiga600FastRamExpansion #4

Open TzOk83 opened 4 years ago

TzOk83 commented 4 years ago

I had a really hard time putting together the OpenKickstartSwitcher and the OpenAmiga600FastRamExpansion in my Amiga 600. They do fit, but I had to cut a corner of the OKS board, which collides with the CPLD socket (this part has no tracks, just the Open Hardware logo). I have also had to cut all the excessive parts of pins from the resistor array and goldpins, and put some kapton tape for the insulation. If the EPROM is soldered onto the board it fits under the keyboard and it is (barely) possible to close the A600 case.

SukkoPera commented 4 years ago

I'm sorry, but as the README states, this project is mainly targeted at the A500, it won't fit cleanly in an A600 even by itself, and I'm sure the RAM card makes things even worse.

I'm going to mark this as "help wanted" and leave it open, in case anyone wants to reshape the board so that it fits better in the A600 (schematics are already OK). Personally I'm not interested in that.

TzOk83 commented 4 years ago

It actually fits the A600 fine, but you can't use sockets under ICs, and you have to trim the goldpin pins about 2 mm, so the connector fits the EPROM socket on the motherboard without any gap.

lovrenco commented 4 years ago

I was thinking of getting this for Amiga600 among with Chipram and Fastram expansion, and now I read it will notfit? Uh, what I mean is, Amiga 600 is ideal computer for casual gaming, since it takes up very little space unlike Amiga 500. If you ad Gotek with FlashFloppy to it, using this kickstart switcher you could have best of both worlds:

  1. With kick 1.3 great compatibility wit ADF-s
  2. With Kick 3 and above great support for Whdload games library on big SD card.

Is there a way to put all 3 addons to Amiga 600?

TzOk83 commented 4 years ago

For 2 ROMs you just need to pull pin 1 (A18) of 27C800 out of socket, and wire a switch to it (to connect the leg either to +5V for upper bank, and GND for lower bank). As KS1.3 is only 256kB, you need to put it twice in one of the 512kB banks.

However, this switcher will fit A600 if you solder EPROM directly to it or solder the switcher board directly to the mainboard, and don't have the top shield (v1.5 and newer units didn't have it from factory).

SukkoPera commented 4 years ago

I was thinking of getting this for Amiga600 among with Chipram and Fastram expansion, and now I read it will notfit?

This is stated pretty clearly in the README:

It will also work on the A600, but you won't be able to place the keyboard back into the case

And yeah. the A600 is small, that's exactly why fitting expansions into it is so problematic.