PAL-1/KIM1

[Kurt Pieper]

Hello Kim 1 fans,

I ordered a PAL-1 on Friday.
The order will be shipped today. Thanks to the PAL-1 developer.
I'm really looking forward to the product.

I'm already 77 years old and still curious.

I'm familiar enough with the 6502 CPU from the C64 and Z80, from the Kaypro 4/84, and from Steve Cousins' excellent boards.

I'm not an electronics engineer, just a hobbyist. My focus was and is programming.

I hope we have a lively exchange of ideas.

Greetings from the Rhine
Kurt

(Text created using Google Translate)

[Hans Otten]

Welcome! You will enjoy the PAL-1 as we all do!

Hans

[Kurt Pieper]

Thanks, Hans.

I've already read some good to very good information on your website.

[GN Liu]

Welcome to our group, hope you will enjoy the kit and bring back some 6502 memories!!!

Liu

[Kurt Pieper]

Hello Liu
Thanks for the welcome.

[Kurt Pieper]

Hi everyone,
I picked up the PAL-1 kit from customs today.

I got to work and soldered.
Tested it with a Siglent SPD3303X-E lab power supply.
The PAL-1 works with the demo program from the USER MANUAL on page 7.
I'm working with 7.5 volts and 0.6 A. The PAL-1 draws 0.32 A for RS 232 and 0.45 A for KEYPAD.

CPU and 6532 temperature are 46 degrees Celsius.

What can I say? It was really fun to build the kit. Great kit and good product.

I like the PAL-1 from Liu.

Best regards from the Rhine
Kurt

This review was created using Google Translate.

[Kurt Pieper]

With the R650C24P CPU, I get better current values.
RS232 = 0.20A, KEYPAD = 0.33A
The lab power supply still delivers 7.5 volts

[Kurt Pieper]

Hi,

Which 27C64 EPROM do you use for testing the PAL-1?
I wanted to create a backup.

I made a copy of the original PAL-1 EPROM.
I've been using MiniPro for burning for years. EPROMs were burned. Verification OK.

Unfortunately, AMD 2764 or Fujitsu 27C64 don't work.
PAL-1 doesn't boot.

Do you have any tips? Thanks for the info.

I've already ordered ROM Expansion V1.2 and have some remaining stock (28C256). I'm curious and, as always, full of anticipation.

Best regards

Kurt

[Ronny Ribeiro]

I'm not sure, but 28C64 are the erasable ones.

I have a bunch of them, but they are all working rebadged ones, so I'm not sure their brand.

I think the 27C are the one time programming ones (didn't check). So if you have some blank ones, they should work.

Ronny

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[Ronny Ribeiro]

Ok, I've made some confusion: 27C are the optically erasable ones. They should work if they are blank.

There are some 27C plastic cases. These are OTP. Once programmed, they're gone.

28C are the EEPROM ones. As I said, I have a bunch of rebadged ones and they all work fine. Erase and reprogram fine.

Ronny

[Kurt Pieper]

Hi,

I have some ATMEL 28C64Bs that aren't working.

I'll order the NSC 27C64Q from A, and those are the EPROMs used in the PAL-1.

Thanks for the info.

Kurt

[Ronny Ribeiro]

Some of my 28C do not program with the T48 programmer but they indeed program with the TL866 programmer...

To view this discussion visit https://groups.google.com/d/msgid/pal6502/76d39b0f-250b-48cf-91d9-1330a7baf2aan%40googlegroups.com.

[GN Liu]

Only the 27C64 works with the PAL-1, but different brands behave differently—some are unstable, and some are unusable. Based on my testing, the National Semiconductor NMC27C64Q with an access time of 200ns to 250ns is the most stable.

Liu

[Kurt Pieper]

Hi,

Thanks for the info.
I already suspected that.
I ordered these EPROMs.
But they're not supposed to arrive until mid-June?

Kurt

[Kurt Pieper]

Hi guys,

Does anyone have information about a working AT28C64 for the PAL-1?
I need the exact name. Thanks for any info.

I have these versions from ATMEL:
AT28C64
AT28C64B

I've been burning EPROMs since around 1982 and have never had any major problems.
Either I could burn the EPROM or I couldn't because it was defective.

According to Liu, PAL-1 doesn't work with every 2764 or 27C64.

Yes, I'm just curious and experimenting with electronics.

I hope we all enjoy the hobby.

Kurt

[Ronny Ribeiro]

As I wrote before I have some rebadged 28C64. They are Atmel AT28C64B and they are working in my PAL-1. You may try one of these, Kurt.

Ronny

To view this discussion visit https://groups.google.com/d/msgid/pal6502/c5ab6e3f-f400-491e-9073-7477ed8db4d7n%40googlegroups.com.

[Kurt Pieper]

Hi,
thanks.

Yes, I tried that.
Is there a way to submit the file?
The monitor program that was installed on your system.
Or do I have to ask the developer?

I don't know.

[Ronny Ribeiro]

I replied you in another conversation where the file is attached. There is a relevant discussion there.
Let me know if you found it.

To view this discussion visit https://groups.google.com/d/msgid/pal6502/e9bde048-5148-40f4-ad94-2cc6ffbc9c23n%40googlegroups.com.

[Kurt Pieper]

Hi Ronny,
thanks for your info.

I found the file.

I was almost sure. It doesn't work either.

I'm waiting for the EPROMs. According to Liu, which ones are the best?

The problem lies with the PAL-1.

[Ronny Ribeiro]

I thought your PAL-1 was working and you just wanted a backup EPROM. Is it working or not?

If you have any available, you can try some 27C256. They should work either.

I tested many EPROMs on the PAL-1 when I was testing the insertion of Wozmon in the monitor and had no problems with their type.

I tested 27C256's, 27C64, 28C64, all worked fine.

To view this discussion visit https://groups.google.com/d/msgid/pal6502/ab42e480-afd1-4b66-aa32-0068d463b99dn%40googlegroups.com.

[Kurt Pieper]

Hello Ronny,

My PAL-1 works with the original EPROM.
It's an NSC 27C64Q.
Liu knows the problem and wrote that some EPROMs are causing problems.
All of them are causing problems for me. Is PAL-1 having a problem?

So, the original PAL-1 works.

But I also want to create my own extensions and burn some EPROMs. So, I'd like to actively work with the PAL-1.

I have other retro systems for programming (C64, Kaypro 4/84, and some Z80/Z180 from S. Cousins).

It's a shame it doesn't work.

Best regards
from the Rhine
Kurt

[Kande Laber]

@Liu: What about the "real" retro EPROMs.
I have a bunch of Mitsubishi M5L2764K, they are unused, I bought them approx 40 years ago.
Because of the programming voltage they can only be read in a TL466, not written.
But I have working EPROM-programmer which is also 40 years old. This can them write too.

Would the Mitsubishi M5L2764K work in the PAL-1

Besŧ regards

[Kurt Pieper]

Hello,

TL466 should probably be TL866.
I have the TL866 CS version, and it can write up to 21V.

I don't have a chip.

The common EPROMs should work with the PAL-1.

My problem isn't burning, the PAL-1 doesn't work?

Kurt

[GN L]

Hi Kurt,

I don’t have a Mitsubishi M5L2764K to test…

> On May 25, 2025, at 6:43 PM, Kande Laber <kande2...@gmail.com> wrote:
>
> Mitsubishi M5L2764K,


Best,
Liu

[Kurt Pieper]

Hello Liu,

I've tested many EPROMs with the PAL-1.

AT28C64B doesn't work either.

Ronny has no problems. It works there. That's how it should be.

If I spend over 100 euros on a board, I expect it to work.

An NsC 27C64 EPROM is arriving in two days.

Let's hope it works.

Kurt

[Ronny Ribeiro]

Kurt,

We always help out our fellow PAL users. Every one that had some problems got a solution in the end.

I understand your frustration, but try to be a little patient and gather all the information concerning the problem you can. This will help us sort out what's going on with your system.

Thank you. 

Ronny

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[Kande Laber]

"TL466 should probably be TL866." Yes, typo, sorry.
In my TL866 it is just not on the list of supported chips.

If you think that the EPROM per se is OK the maybe you have bad connection in the chip socket etc.
At least I had such a problem in the beginning.

[Hans Otten]

Kurt,

"If I spend over 100 euros on a board, I expect it to work."

Your PAL-1 works as you reported above. 

It even works when you inserted a WD65C02.

So that is 100 euros well spent!

Hans

[Kurt Pieper]

Hello Hans,

My PAL-1 works. That's right, but not to the extended extent.
It's just a shame that no EPROM works.
I would have liked to have some small tools in the EPROM.

I'm still getting the ROM EXPANSIONV1.2 board.
Then additional bytes will be available.

I think the PAL-1 is a good board. It's also a lot of fun.

Kurt

[Voyageur]

Hi Kurt,

I'm not a specialist, but I've made many SBC and  I'll try to help for this problem...

Your PAL-1 works with the original ROM, right ? And when you try a new EEPROM, it doesn't ?

So the problem is coming from the new ROM. Nothing to do with your Board...

The code inside new ROM doesn't seem to be workable for the PAL-1 board.

So, IMHO, the problem is coming from the EEPROM (EPROM, ROM, whatever...) or from the Programmer.

I can't imagine all your chips are dead and usefulness... But you could have one or two...

Maybe it's coming from your EEPROM burner...

With your Minipro and TL866 CS, could you check if your new ROM is the exact copy of the one from the PAL-1 board ?

Should be the same between $000 and $07FF. I joint attached my copy of Liu's original monitor code (Hope he can let me do that)..

What is your OS ? I guess it's Linux... but be aware that your Programmer is obsolete.

The XGECU website says :

" Please note that the TL866A/CS be stopped delivery in February 2018 "

And the only Windows software they can provide is V6.85, marked as OLD.

So no more support from the manufacturer of your programmer.

I use the TL866II or the T48 and I can program all of my ROM or EEPROM, under Linux or Windows.

I also use RAMTRON, ferromagnetic memory, like the FM1608 (8 KB) with no problem...

Maybe in this group you could find some people using the same 'old' Programmer...

Waiting for your answer. Cheers from Australia.

[Kande Laber]

 There is the "KIM-1 Monitor (6530-003 & 6530-002) Binary image" on Liu's website:

http://pal.aibs.ws/assets/kim.bin

 The two files are different in length and content:

$ ls -ltr NM27...@DIP28.BIN kim.bin
-rw-r--r--. 1 xxxxxxx xxxxxxx 2048 27. Mai 09:06 kim.bin
-rw-r--r--. 1 xxxxxxx xxxxxxx 8192 27. Mai 08:54 NM27...@DIP28.BIN

$ sha256sum kim.bin
4fa2b5fab0e27b6015e2475fb9b483f10e81c2df4524f1d5b74945dcd6a38723  kim.bin
$ sha256sum NM27...@DIP28.BIN
4b960554c693ac7623704e95044ca60d0955d609ce2d1e3001dd7f29043563ec  NM27...@DIP28.BIN

i.e. NM27...@DIP28.BIN is filled with 0xff beyond 0x07ff.

[GN Liu]

The KIM-1 monitor only occupies 2K, starting from address 0x0000. The space beyond the first 2K is ignored by the system.
I think you can checksum your ROM content against voyageur6502’s image to see if there are any differences.

Liu

[Kande Laber]

Yes, that is for sure.

The point I would like to raise is as follows:

When I read Kurt "... I would have liked to have some small tools in the EPROM."
If somebody tries to use the "free space" in the monitor Eprom to place his "small tools" there, the 'small tools' will not be reachable and somebody will be disappointed.

[Kurt Pieper]

Hi guys,

Thanks for your help.

I found the error last night.
If I load the kim.bin file and burn it to a 2864 or 2864B, it works.

I discovered that the NSC 27C64Q EPROM isn't supported by my MiniPro. 

The ID can't be set correctly.

When reading the EPROM, I disabled the ID query.
The kim.bin file and my pal-1.bin are not the same.

That was my mistake. Human error (Cicero).

Today I received a file attachment from Voyage. It works, too.

All good. The discovery continues.

Thanks again

Kurt

[Ronny Ribeiro]

One more troubleshooting with a happy ending in this group. 

And a lot of lessons learnt!

Thank you all!

Ronny 

To view this discussion visit https://groups.google.com/d/msgid/pal6502/fa7475d4-452a-40fb-9a52-fdbf9eeb94f0n%40googlegroups.com.

[Hans Otten]

The KIM-1 has 2K in ROM, in two 1K maskable ROMS of the 6530-002 and 6530-003.
The 6530-002 implements a TTY interface, a keyboard interface (hence the name Keyboard Interface Monitor) and 6 7 segment LED displays.

6530-003 is an audio cassette recorder extension of the KIM monitor. This one is not using all the 1K of the available space, so you can add software there yourself in a KIM-1 clone.
A good example is the Apple 1 monitor, 256 bytes fit fine. Another example is the boot code for the K-1013 floppy disk controller by Eduardo Casino. 
If you do not use the audi cassette recorder interface you can use the whole 1K for something useful, as Bob Applegate did for the Corsham KIM clone, integrated with the KIM-1 monitor.  

There are several versions of the KIM-1 ROMs floating around.

The most common ones on the internet are the binary output of the assembler source, typed in a long time ago.

The least common but only correct versions are the ROM dumps made by me and Dwight Elvey.

On the KIM-1 ROM dump done by Dwight Elvey, the filler bytes (unused locations in the ROM) are filled with $00.
I confirmed the dumps of Dwight (who were faulty in other parts) by making a dump of the ROMs in my own KIM-1.

The other set, found all over the internet, is the result of assembling the source (see below) in which the assembler used $FF for the filler bytes. It makes sense to use $FF, since EPROMs can be programmed to make '1's to 0's. Functionally the filler byte is irrelevant.

The ROMs in the PAL-1 are the KIM-1 ROMS with fillerbyte $00 and the text KIM replaced with PAL. 

See also KIM-1 ROMs – Retro Computing

and

KIM Monitor KIM clone – Retro Computing

[Kurt Pieper]

Hello Hans,

Thanks for this info.

This is exactly what I'm looking for.

I'll have some exciting tasks ahead of me now.

Best regards from the Rhine.

Kurt