#kim1 — 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!

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!

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

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!

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!

If all goes according to plan, I'll have two weeks off work at the end of this month.

Was thinking of writing something for the #KIM1 again, as I found the two previous experiments rather fun.
Also I now have a solution in search of a problem: 1MB of RAM on that machine is ridiculous and I'd like to find something to use at least a slice of that expansion.

Would have been easier if I also had the time to design a graphics card for the computer.

If all goes according to plan, I'll have two weeks off work at the end of this month.

Was thinking of writing something for the #KIM1 again, as I found the two previous experiments rather fun.
Also I now have a solution in search of a problem: 1MB of RAM on that machine is ridiculous and I'd like to find something to use at least a slice of that expansion.

Would have been easier if I also had the time to design a graphics card for the computer.

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.

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.

@eduardocasino Eduardo, happy to see you here! Thanks for your #KIM1 work, I always wanted one and now I got one thanks to that. I'll also build a few more of your boards in the future (eyeing the floppy controller).

About that feature, my advice is to make it optional behind a jumper, so one can detach from the serial port without resets, if so desired.

@eduardocasino Eduardo, happy to see you here! Thanks for your #KIM1 work, I always wanted one and now I got one thanks to that. I'll also build a few more of your boards in the future (eyeing the floppy controller).

About that feature, my advice is to make it optional behind a jumper, so one can detach from the serial port without resets, if so desired.

Here it is, released #MOStermind for the #KIM1:
https://codeberg.org/hkzlab/MOStermind_KIM-1

I really wonder if this works fine on a teletype. Should someone in a near or distant future ever try it there, please let me know.

A video terminal should work fine though, you just need that, a KIM-1 and a RAM expansion that fills at least 2KB (we're using a bit less than 1.5KB) starting from 2000h.

Enjoy!

Here it is, released #MOStermind for the #KIM1:
https://codeberg.org/hkzlab/MOStermind_KIM-1

I really wonder if this works fine on a teletype. Should someone in a near or distant future ever try it there, please let me know.

A video terminal should work fine though, you just need that, a KIM-1 and a RAM expansion that fills at least 2KB (we're using a bit less than 1.5KB) starting from 2000h.

Enjoy!

If wife has no pressing work for me at the #farm, I'll start work on releasing #MOStermind for the #KIM1.

If wife has no pressing work for me at the #farm, I'll start work on releasing #MOStermind for the #KIM1.

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

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

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.

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.

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.

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.

The makefile for #MOStermind generates a raw binary, a paper tape image and a prg file you can load via a IEC drive (an SD2IEC in my case).

It's rather fun to see the #KIM1 load and start the game from there.

In other news, I think a first version of the game is ready. It's a real pity I don't own a teletype to try it there (if someone wants to try it, let me know! You need a KIM-1 and at least 2KB of RAM at 0x2000), but it should work there too.

I should probably increase the number of symbols from 4 to 6 just to make it a bit harder. Something for another day though.

Might want to start preparing the repo and leaflet next.

The makefile for #MOStermind generates a raw binary, a paper tape image and a prg file you can load via a IEC drive (an SD2IEC in my case).

It's rather fun to see the #KIM1 load and start the game from there.

In other news, I think a first version of the game is ready. It's a real pity I don't own a teletype to try it there (if someone wants to try it, let me know! You need a KIM-1 and at least 2KB of RAM at 0x2000), but it should work there too.

I should probably increase the number of symbols from 4 to 6 just to make it a bit harder. Something for another day though.

Might want to start preparing the repo and leaflet next.

Broadband is down, but my backup is decent enough to allow me to upload this!

I made some progress with #MOStermind, a mastermind port for the #KIM1, using the teletype interface. This was born more or less as a joke with a work colleague.

You can see the current version running under #MAME here (but I have tested it on my KIM-1 clone already.

There's plenty of optimization still to do, but the game is currently fitting in 1342 bytes, including both logic and text.

Broadband is down, but my backup is decent enough to allow me to upload this!

I made some progress with #MOStermind, a mastermind port for the #KIM1, using the teletype interface. This was born more or less as a joke with a work colleague.

You can see the current version running under #MAME here (but I have tested it on my KIM-1 clone already.

There's plenty of optimization still to do, but the game is currently fitting in 1342 bytes, including both logic and text.

A few weeks ago I was talking about the #kim1 with a colleague, and he said that a port of mastermind on the machine would have been cool.

We were thinking of doing it via the keypad, but I wanted to experiment with the serial interface, so here I am, playing around with it.

Pity my air conditioning died. And it was installed just a few months ago, had almost no use. Let's see what the tech has to say tomorrow.

Right now, enough programming. I'm melting.

A few weeks ago I was talking about the #kim1 with a colleague, and he said that a port of mastermind on the machine would have been cool.

We were thinking of doing it via the keypad, but I wanted to experiment with the serial interface, so here I am, playing around with it.

Pity my air conditioning died. And it was installed just a few months ago, had almost no use. Let's see what the tech has to say tomorrow.

Right now, enough programming. I'm melting.

Sent the Rev.0 of the #KIM1 RAMpager to #PCBway for sponsorship approval.
If they greenlight it, I'll also prepare a mouser cart for the build

Sent the Rev.0 of the #KIM1 RAMpager to #PCBway for sponsorship approval.
If they greenlight it, I'll also prepare a mouser cart for the build

I think I'm almost ready to send the prototype of the RAMpager for the #KIM1 to the fab. Probably going to do that next week, including Mouser order for components. Currently a bit in a pinch with vet expenses.

I changed the circuit that handles the /CE signal for the SRAMs to try avoid parasitic currents from the battery to the GAL22V10. Tried to cut it off using mosfets.

I also added the option of using either a 1N5917 to power the SRAMs if you wish to stay THT or a PMEG2010ER (SMD) that has lower leakage current.

We'll see if I made a mess doing this. I probably have. But you fail and learn I guess...

I think I'm almost ready to send the prototype of the RAMpager for the #KIM1 to the fab. Probably going to do that next week, including Mouser order for components. Currently a bit in a pinch with vet expenses.

I changed the circuit that handles the /CE signal for the SRAMs to try avoid parasitic currents from the battery to the GAL22V10. Tried to cut it off using mosfets.

I also added the option of using either a 1N5917 to power the SRAMs if you wish to stay THT or a PMEG2010ER (SMD) that has lower leakage current.

We'll see if I made a mess doing this. I probably have. But you fail and learn I guess...

phew, just got back home.
I have only one hour before I need to depart again for the restaurant (dinner with colleagues today). Enough to do some work on the silkscreen of the #kim1 paged RAM card.

I need to think of a name for it...

phew, just got back home.
I have only one hour before I need to depart again for the restaurant (dinner with colleagues today). Enough to do some work on the silkscreen of the #kim1 paged RAM card.

I need to think of a name for it...

Initial routing of the paged RAM board for the #KIM1 is now complete.

The work is not done though, I still need to:
- Tweak the traces
- Prepare zone fills
- Reorganize the silkscreen labels
- Draw instructions for all the switches and jumpers
- Maybe a nice logo for the empty space under the LEDs?

Still, it doesn't look too bad, right?

Initial routing of the paged RAM board for the #KIM1 is now complete.

The work is not done though, I still need to:
- Tweak the traces
- Prepare zone fills
- Reorganize the silkscreen labels
- Draw instructions for all the switches and jumpers
- Maybe a nice logo for the empty space under the LEDs?

Still, it doesn't look too bad, right?

Time to start laying out the paged SRAM board.
I'm using the same outline as the MTU RAM/ROM expansion card by Eduardo Casino, but I suspect I'll have to enlarge this a bit. #kim1

Time to start laying out the paged SRAM board.
I'm using the same outline as the MTU RAM/ROM expansion card by Eduardo Casino, but I suspect I'll have to enlarge this a bit. #kim1

Working on the equations I'll be using for the 22V10 PLD that'll do most of the decoding on the paged RAM card I'm designing (#kim1).

As usual, I like to work on paper first.

Working on the equations I'll be using for the 22V10 PLD that'll do most of the decoding on the paged RAM card I'm designing (#kim1).

As usual, I like to work on paper first.

I think I can say that the work on the paged RAM MTU card for the #KIM1 has officially started.

I'm aiming at a 512KB expansion with a window of 4KB. My intention is to allow independent selection for the read and write banks (e.g. you can write to bank 1 while reads go to bank 2).

I think I can say that the work on the paged RAM MTU card for the #KIM1 has officially started.

I'm aiming at a 512KB expansion with a window of 4KB. My intention is to allow independent selection for the read and write banks (e.g. you can write to bank 1 while reads go to bank 2).

Jotted down a few pages of notes on #kim1 memory decoding and how I'd organize the paged RAM card I'd like to implement.
Time to sleep on it and look at them again tomorrow morning.

Jotted down a few pages of notes on #kim1 memory decoding and how I'd organize the paged RAM card I'd like to implement.
Time to sleep on it and look at them again tomorrow morning.

This is impressive.
What you see in photo is a #sd2iec identical to the one I assembled for my C64 and C128.

And it's listing files.
From the #KIM1.

And probably an 1541 would work just as well.

This is impressive.
What you see in photo is a #sd2iec identical to the one I assembled for my C64 and C128.

And it's listing files.
From the #KIM1.

And probably an 1541 would work just as well.

There, released the playback tool for #KIM1 tape images: roulant.
https://codeberg.org/hkzlab/KIM-1_roulant

Time to go out for a walk a bit.
If I have enough time later today, I promised someone to clarify a bit the build procedure for the MiniPerformer+ accelerator, mailing with a few better pics in the README.

There, released the playback tool for #KIM1 tape images: roulant.
https://codeberg.org/hkzlab/KIM-1_roulant

Time to go out for a walk a bit.
If I have enough time later today, I promised someone to clarify a bit the build procedure for the MiniPerformer+ accelerator, mailing with a few better pics in the README.