djglish Posted April 11 Share Posted April 11 I have a Mega ST motherboard that I'm trying to get working again. I had it mounted in a tower PC case. It was a little touchy on starting and sometimes crashed. I think it may have been due to the motherboard being mounted vertically instead of horizontally. I messed up the floppy drive connector on the motherboard and just had a friend help put a new floppy connector on the board. There is some type of modification to the motherboard. I'm including a picture of the wiring. Quote Link to comment Share on other sites More sharing options...
snarkdluG Posted April 12 Share Posted April 12 It's the Mega ST blitter patch. It usually fitted on a small board soldered directly to the 68k chip. 1 Quote Link to comment Share on other sites More sharing options...
djglish Posted April 12 Author Share Posted April 12 Thanks for the information and the link Quote Link to comment Share on other sites More sharing options...
macsonny Posted April 25 Share Posted April 25 So I removed all the mods today and the unit worked but was a bit flakey and would bomb if the 68000 was tapped. I removed the 68000 and found 4 pin which were broken and not the full length meaning their contact with the socket was not great. I built new pins from headers, re-installed the 68000 and the unit is rock solid now. Thanks for all the input. 1 Quote Link to comment Share on other sites More sharing options...
djglish Posted May 4 Author Share Posted May 4 I had a friend help me replace the floppy drive connector on the board. I damaged it trying to get ta longer floppy cable attached. Put in a standard 34 pin connector (like on a PC motherboard). With the motherboard sitting horizontally I reseated all of the socketed chips and the board boots up and the floppy drive works. Now I need to figure out which chips seem to work loose and cause the system to bomb when I mount it vertically. It's in a tower IBM type case. I'm also going to reinstall the cable from the onboard ACSI connector to the ICD ADSCSI+ that is mounted in the case. Once the SCSI is working again I need to decide what I want to connect to it. I used to have a hard drive, CD-ROM drive, and tape backup in the past. I probably won't bother with the tape backup drive and may use a Syquest drive or an Iomega Zip drive instead. These are all drives that I still have. I wish that I had a 1gb Jazz drive to compliment the hard drive. Anyone have other thoughts on what to add? Quote Link to comment Share on other sites More sharing options...
macsonny Posted May 5 Share Posted May 5 On 4/12/2024 at 9:08 AM, djglish said: I have a Mega ST motherboard that I'm trying to get working again. I had it mounted in a tower PC case. It was a little touchy on starting and sometimes crashed. I think it may have been due to the motherboard being mounted vertically instead of horizontally. I messed up the floppy drive connector on the motherboard and just had a friend help put a new floppy connector on the board. There is some type of modification to the motherboard. I'm including a picture of the wiring. What's the wiring details for a Blitter patch? Quote Link to comment Share on other sites More sharing options...
snarkdluG Posted May 6 Share Posted May 6 11 hours ago, macsonny said: What's the wiring details for a Blitter patch? Quote Link to comment Share on other sites More sharing options...
Like us on Facebook
Follow us on Twitter
AtariAge on Instagram
Watch us on YouTube
Chat on Discord
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.