Recent content by nestor

Very interesting, I made a 2MB module ten years ago (totally hand-made) I was planning to make a new design, with freely downloadable gerbers so anyone can build them. Are you planning to share yours?

Well, in fact it is a IBM 5162 XT/286 motherboard what I have right here, but it is the same for the purpose. I'm trying to understand "the magic" that makes 8 bit cards work in this 80286 motherboard. How is a 16 bit access cycle splitted into two 8 bit cycles? I can't find any reference in the...

Does anybody know if these two computers share the same planar? I think both have the same chipset as the PS/1 model 2121, including the integrated video controller of the SVGA/A adapter. Partial photo of the PS/1 board: http://i.ebayimg.com/00/s/OTAwWDE2MDA=/z/dqkAAOSw~bFWQdai/$_57.JPG...

My 5160 has an IBM 8088. Was that common?

I'm looking for a IBM PS/1 2121 model motherboard. I'm located in Spain.

I'm looking for the datasheet of these IBM DRAM ICs. They sum 2 MByte onboard ram in a 386sx motherboard, so I think they are 1Mx4bit Any tip or info would be good! Thank you.

I was running Checkit 3.0 System Board tests in my IBM PS/1 model 2011 (286 @ 10 MHz) and I noticed that the system made three beeps while doing "CPU Protected Mode" test. The test passed, but after finishing the remaining tests the keyboard seems to be locked. I read somewhere that the 286...

I'm trying to connect a Windows 3.0 environment to internet. I have tried with Trumpet Winsock 1.0 and 3.0 but it seems that only work correctly on Windows 3.1 and 3.11. Is there any winsock implementation for Windows 3.0?

I recived today a Philips P2814 keyboard that seems to support both XT and AT protocols (it has the standard AT layout but no XT/AT switch). I plugged it to my IBM 5160XT and it works like a charm, but I can't get it working in a generic Turbo XT clone. I tried some time ago an IBM Model M...

I'm looking for a ISA 16 bit memory upgrade board for a 286. Features like LIM EMS 4.0 support, use of SIMMS instead of DIP RAM ICs, or short PCB length will be valued positively.

Browsing the net I have seen some 5160 computers with two half height floppy drives instead of a full height one. This, for example. I tried to put two half drives in my 5160 but I found that there are no screw holes for the upper half height drive. I would prefer not to drill the case, is...

I'm looking for a IBM 486SLC /2 /3 upgrade module (I think they were for PS/2 machines). Or maybe a 486SLC motherboard will be OK.

This is the second time that my IBM PC 5150 does this : The drives are the standard Tandon DSDD 360k: Is this a standard ageing problem?

I have found a suspicious electrolytic capacitor, looks a bit blown... and seems the main filter (220 uF, 400v)

Today my backup PS/1 monitor has started to fail. All video modes except 640x480 have a sync problem that makes the monitor unusable. But in 640x480 the image is sharp, clean and free of any sync problems. I'm totally lost, if the VGA cord was in bad state the sync problem would affect all video...