#rampager — Public Fediverse posts

It's time to release the #RAMpager! An MTU banked RAM expansion card for the #KIM1 computer.

This board allows up to 1MB of memory via a 4KB banked window (with different read/write controls, so you can write to a page while reading from another!).

https://codeberg.org/hkzlab/KIM-1_RAMpager

As usual, thanks to #PCBWay for sponsoring the project via PCB production.

If you wish to donate even small amounts, it's always appreciated and you can do so via ko-fi.com/hkzlab
I use that mainly to pay components for these projects.

Enjoy!

Started writing the README for the #RAMpager board.

God I hate writing these. Really.

I think that's it for today. Dead tired.

The #RAMpager behaved correctly, I'm almost tempted to say I can start writing the README in preparation of a release.

I've yet to find what to do with all that memory, but the main objective was to test the bank switching circuitry. I think it'll come in handy once I'll work on a 6845 based video card.

There are also many other things that would be cool to fit on a KIM-1 board: audio (e.g. a cut down Apple 2 mockingboard would be nice), proper serial ports, a nice ASCII keyboard input.

Still, I want to write something that uses the RAMpager first.

Here is the fully assembled #KIM1 #RAMpager, and no bodges in this revision (for now)!

Testing the new revision of the #RAMpager with my #KIM1 clone plus MTU motherboard!

If you are observant, the lit 7 segs indicate that the KIM-1 reset successfully, which means that the logic on this board correctly handles internal/external memory decoding.

This board can (optionally) live alone on the MTU bus, if one so desires!

The rev. 1 of the #RAMpager prototype is now assembled. I just need to transfer all the ICs from rev. 0, add a 74'133 and it's good for testing.

Except I won't do it today. About to go away for errands that will take what is left of the day. Plus I'll be out most of tomorrow too (hottest day of the week, thanks BTO) and I don't want to ruminate on this in case something is broken.

I'm also exceptionally tired. Seems like I need half a day of sleep to recover, and I only get 5.5h/day at best...

So, probably tomorrow in the evening, or Thursday.

New board revision batch for the #RAMpager acquired! This was also sponsored by #pcbway.

I'll get one assembled and tested in the coming days, can't get to it today as the day is already full.

Good news of the day: The new rev of the #RAMpager will probably be delivered today

Bad news: I really need go get off my ass and update ALL my hardware repositories with a non-commercial license, plus instructions on how to contact me for collaborations... Mostly to discourage fuckers that love to waste my time.

It's simple, really:
- Do you want to distribute my work at a loss or with zero gain? Go for it.
- Do you want to profit from it? Contact me first and send 5% of the money, please.
- Not going to do customer care service for your customers.

It's a hobby. If I decide to turn it into a job, I'll start selling kits myself

The good news for today is that, at least, rev. 1 of the #KIM1 #RAMpager has been submitted for production at #PCBway.

There, that's it. That's the peak of the day.

And I still have several hours of bullshit to endure.

If I'm getting the #KIM1 memory decoding right, to have the #RAMpager work as a single card on the MTU bus I need to do two things:
- Assert /DECEN when the address is in the range 0000h-1FFFh. Easy, I already have everything I need on my current card
- Assert K7 when the address is in the FFFxh range (vectors) so that the KIM-1 can react and remap them.

The second point requires at least a 74LS133 for the decoding (plus a diode). Not a problem, but a reroute of the board will be necessary.

So next steps:
1. Work on a rev.1 with bugs fixed but without this feature
2. Add this feature in a rev. 2

My very healthy approach to life makes me go suspiscious and paranoid every time something works as I'd like.

In other news, the #RAMpager is still running...

The test is looping on the #RAMpager.
Nothing fancy: it exercises the I/O by writing and reading the registers.
It also fills and reads the whole megabyte with various patterns.

It's still not robust enough as a test: it should fill the banks with different patterns and check that they do not overwrite each other. Next thing in line.

FTTH got fixed yestedarday: wasps made a nest in a very annoying place. Sorted now.

And I now have a few days off. Doesn't mean a lot of free time as there are loads of things to take care of in the farm, but still, more than usual.

I'll spend a few hours in the morning doing the following:
- Improvements to the #RAMpager PLD (forgot to explicitly put the data buffer in high impedence while reset is asserted)
- Start writing an exerciser tool for the expansion. Mainly to test the paging functionality
- Maybe watch a few videos. I have weeks to catch up.

Let's write a little thread about the fuckups I made with the #KIM1 #RAMpager.

First, the good news: the board is behaving decently now. I still need to do some heavy testing to hammer it, especially regarding the access to the registers that hold the current read/write pages but, for now, it seems they're fine accessed from the monitor.

Debugging the #KIM1 #RAMpager.
Enjoy the mess.

Prototypes for the #KIM1 #RAMpager board were delivered, and components too.

Hopefully this week I'll have some free time to start the build. And I'm sure this will end up requiring copious swearing, reprogramming and bodging to get up and running.

Guten Abend meine werten #Mastonauten.

Ich war Mal wieder in den örtlichen Gameläden unterwegs und bin mit zwei kleinen Schnappern zurückgekehrt 😊👍

Der #Rampager von #Borderlands3 als ca 40 cm großes #Räuchermännchen 🙂 wenn ich ihn anwerfe kann ich bei Bedarf gerne einen Clip hochladen 👍 (Der Rauch kommt aus seinem Schlot, er hat eine kleine Tasse unter dem "Hintern" 🤣)

Zudem kommt Deus Ex Human Revolution für die Ps3 👍

#gaming #game #schnapper #retrogames #figuren #sammeln