Tiny update. The project isn't abandoned. Due to personal reasons, I've got just no nerves to continue at the moment.
All parts are stored safely for the day I'll continue finishing it. I hope you don't mind.. 😀

Update. I may go another route and try installing the RAM on a daughter board first.
Anyway, it still takes a little while until I've gathered enough mental energy to continue.
Over the Christmas holidays, maybe ? 😀

Most certainly!

Yay! 😁

Sorry to keep you waiting.. I hope that I can finish this project this easter.
- I recently got an old oscillograph (scope) that might be helpful for troubleshooting later on. 😀

ibmapc wrote:

This looks great! Have you had a look at this? http://www.vcfed.org/forum/showthread.php?281 … quivillent-PROM This is a very […]
Show full quote

This looks great!
Have you had a look at this? http://www.vcfed.org/forum/showthread.php?281 … quivillent-PROM
This is a very nice write up about the same project http://www.vcfed.org/forum/showthread.php?626 … d-Portable-5155

This provides UMB in the same regions as your project. The advantage for your project is that it should work on clones as well as the IBM 5160.

As always, I'll provide a programmed GAL to anyone interested in trying this mod for the cost of shipping!!

Greg

Hey Greg! Not sure if you've got PM's disabled or if I'm too much of noob or if some sort of AdBlock is disabled, but I too am interested in the GAL required for the upper memory area on an original XT. Hoping you've still got the chips and capabilities.

I really like the RAM extension projects for older machines. It's a lot of headache at first but it really teaches you to take advantage of every opportunity for more performance.

MrSmiley381 wrote:

Hey Greg! Not sure if you've got PM's disabled or if I'm too much of noob or if some sort of AdBlock is disabled, but I too am interested in the GAL required for the upper memory area on an original XT. Hoping you've still got the chips and capabilities.

I really like the RAM extension projects for older machines. It's a lot of headache at first but it really teaches you to take advantage of every opportunity for more performance.

I tried PM a user the other day. I could not find the option for it. I don't think this site has a PM system. That or I'm Mr magoo and can't find it.

Parts man wrote:

I tried PM a user the other day. I could not find the option for it.
I don't think this site has a PM system. That or I'm Mr magoo and can't find it.

Hi, Vogons has a PM system. Not sure how many postings are currently required for someone to have before it becomes accessible.
Here's the icon that you usually can click to get into the PM editor. 😀

I actually was able to do a PM from the user control panel.

That being said, that "message" icon very clearly screams "profile". It's a silhouette of a person's head. A PM icon should be something like a text bubble!

Jo22 wrote:

Sorry to keep you waiting.. I hope that I can finish this project this easter.
- I recently got an old oscillograph (scope) that might be helpful for troubleshooting later on. 😀

Ok, so the little oscillograph is working.. I tested it with a discriminator output of a simple Hellschreiber modem that I made for my XT.
- I'll try to continue with the project a little bit, maybe next week already. 😀

Little update. I decided to build a little shield for the RAM chip, to make sure I will not mess up the wiring on the ISA card.
Maybe I can get a few parts on Friday or so. I'll post some pictures once I've got things together. 😀

Edit: Got them. 😀

Update.

Hi everyone! Just worked a bit on the daughter card so far.
- It's not finished yet (-I lost that pin bar-), though.

Anyway, I've attached some pictures for you! ^^

Update. A little bit of progress again. Next station - wiring.

Update. Attached the wires for data.

Must be frustrating to see all the required components slowly trickle in by mail. 😉

Keep us updated, Jo!

digger wrote:

Must be frustrating to see all the required components slowly trickle in by mail. 😉

Hah, yes. It kinda is. 😅 I often visit a local electronics shop (Radio Shack type of shop), which has all the stuff needed.
Well, almost. There you can get solder flux, soldering stations, NE555 timer ICs, LM386 amp chips and such. Even micro controllers since a year or two.
However, some of the classic parts are nolonger available. Like popular radio tubes, 40xx series ICs (predecessor of 74-something), PIC µCs,
certain RF plugs (no N connectors), AM/FM radio ICs, mixer chips, old SRAM (static RAM), DRAM, parallel EPROMs (27xxx), ..

digger wrote:

Keep us updated, Jo!

I will. 😁

Update. Good news, I finished the wiring part (I think so). 😀

Small update. One of the chips I ordered turned out to be of a wrong type. 🙁
Got an 78LS08P instead of an 78LS08N. I'll try to get hold of the right type asap.

Jo22 wrote:

Small update. One of the chips I ordered turned out to be of a wrong type. 🙁
Got an 78LS08P instead of an 78LS08N. I'll try to get hold of the right type asap.

Aw, that's frustrating. Don't lose motivation now! 😀

^Thanks! 😀 I got the missing chips now via mail. I'll continue soon.