560Z Build thread

[glitch]

I got my 12-bit memory board up and going last night. It's got a 12-bit lamp register on it as well, addressable at any byte location in the 64K address space. I'll do a separate writeup on it in another thread.

Tracking says the 74LS125s should be in today, so hopefully I can at least get the porthole functionality tested.

[glitch]

IT LIVES!

I spent most of today hacking on the 560Z board. I got the 12-bit porthole going first, took a bit as the manual doesn't tell you that you need IC CC installed if you want to be able to write to the 4K exposed in the porthole. After that, I plugged in a Z80 and tried to get it running the test code in the manual. Turns out I had a dud Z80 With a good one installed the test code ran no-problem, as did a little hand written code to push data to the lamp register on the new memory board. I plugged in an IM-6100 and pretty much determined that at least the first one I tried is dead. I'll recheck the soldering on it later -- it's stuffed into a machine pin socket and soldered in, since half of the legs were rotted off by that corrosive black foam everyone loves so much.

Anyway, the second IM-6100 works! And the 560Z board works! And the 12-bit RAM board works! I made a (low-res, poorly focused) video with our old digital point-n-shoot:

https://www.youtube.com/watch?v=ZYbGXHJST8U

The IM-6100 is running a little loop that increments the accumulator and stores it to the lamp register. Storing of course clears the accumulator, but I have the lamp register mapped over RAM, so I just read the value back out of it. My first foray into PDP-8 code, it's certainly different, but it's still just machine code. Very happy that this seems to be coming fully together! Now if only I could find more IM-6100s...I'll test the remaining 3 tomorrow.

[Klyball]

Great Work Glitch,

to save every one having to type it out,Here is the IOT part of the driver asm it has a bit of code i started to handle the memory management,Please feel free to fill in the blanks

IOT3400.zip

(2.62 KiB) Downloaded 1267 times

[glitch]

Had time to do a full writeup on building the 560Z:

http://www.glitchwrks.com/2017/02/26/osi-560z-build

[glitch]

GOOD NEWS, EVERYONE!

I've found a component supplier with IM-6100s in stock! And they have several hundred in the system! They're checking to make sure the items are actually there, and getting me a bulk discount quote put together.

[pbirkel]

Whoot!

[dave]

I'm attaching an IM6100 memory extension app note that may be useful. Also, another appnote on subroutines calls (usually self-modying code) from ROM, which may be less useful on a 560z system with no SYS ROM, but still interesting. I have another I'm trying to scan without destroying on adding a serial peripheral to the 6100.


IM6100 CMOS Processor Memory Extension
ROM Based Subroutine Calls with the IM6100

[Jeff]

Great work, guys!

/Jeff

[Klyball]

Just wondering if anyone else got there 560z going and if you wrote any code for the 6100 like mem management or disk support.

[glitch]

I'm dropping off parts at VCF Midwest with another OSI hacker who's working on building up a 560Z. No one else has contacted me with results from 560Z builds, tho. I haven't had much time for OSI hacking lately