Scrumpel8 an 6809 SBC

An 68B09 SBC with 16KB ROM and 32KB RAM, 8 bits I/O and 2 serial ports @ 115200 baud.

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This is a small 68B09 system in two versions: 8a 68B09P, 8b 68B09ES

This computer can run Microsoft BASIC and the Scrumpel monitor originally made for 68HC11 but ported to 6809. 

I also wrote a Forth for it.

Nforth evolves, here the next version:

This is the newest one with extra features


Manual of the Scrumpel monitor

Adobe Portable Document Format - 229.04 kB - 10/01/2021 at 18:42



This is my own created Forth, Nforth for 6809. It loads at $0100 and runs on that address also. You can load it with the loader of the Scrumpel monitor. I removed a datastack check for speed reasons. This is a version which uses USP in stead of IX and I removed an error in the word dump.

- 14.55 kB - 04/20/2021 at 07:36



On request, the scrumpelmonitor sourcecode. I use ASL as crossassembler.

asm - 17.71 kB - 04/09/2021 at 06:14



A game called othello for the 6809 computer. It resides at $3100 and is loadable with the intelhex loader from the monitor. Its startaddress is $3100

hex - 6.58 kB - 03/31/2021 at 17:05


New gerber files using Scrumpel8bV1.1 schematic.

Zip Archive - 146.52 kB - 02/17/2021 at 08:02


View all 11 files

  • 1 × 68B09P Scrumpel8a CPU
  • 1 × 68B09ES Scrumpel8b CPU
  • 1 × 74HCT73 Scrumpel8b Logic ICs / Flip-Flops, Latches, Registers
  • 13 × Capacitor 100nF Scrumpel8a 12, Scrumpel8b 13 Ceramic Capacitor
  • 2 × Capacitor 15pF Scrumpel 8a Ceramic Capacitor

View all 31 components

View all 2 project logs

  • 1
    ERRATA 68B09SE in Scrumpel8b

    Pin 39 TSC of the 68b09 must be connected to ground to work properly. In version 1.1 this is solved..

View all instructions

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Nick Brok wrote 04/27/2021 at 12:49 point

On github the monitor and nforth source-code are published.

  Are you sure? yes | no

Nick Brok wrote 04/20/2021 at 04:27 point

Nforth is a project in progress, I placed the hex file because it can be used for this Scrumpel 8 system. It has special words for the I/O port from Scrumpel. It is my own Forth dialect and is not fully compliant with any Forth standards. It is still experimental also.... It is not optimized for use in 6809 yet,  because I ported it from my 68HC11 version. I use the X register as datastack, but in 6809 you could better use the user-stackpointer.....  It is subroutine threaded, so I can use calls to words and machinecode. As long it's experimental, I won't post the sourcecode..... I don't want to publish incomplete or faulty sourcecode.

  Are you sure? yes | no

Travis Bemann wrote 04/25/2021 at 18:14 point

With my Cortex-M Forth, zeptoforth, I keep it on GitHub and continually update it there so people can see the changes to my code - it is not going to be a finished product for quite some time, if ever, and I am not going to wait for then before I let people see my code (especially since much of the zeptoforth environment is actually written in Forth).

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Travis Bemann wrote 04/19/2021 at 22:29 point

Do you have source code for NForth?

  Are you sure? yes | no

Nick Brok wrote 04/09/2021 at 06:18 point

On your request I publiced the sourcecode of the Scrumpel monitor program.  Have fun with it. 

  Are you sure? yes | no

Scott wrote 04/08/2021 at 21:12 point

Hi Nick:

Nice work. :)

I'm searching for monitors for my own Grant Searle'ish 6309SBC and SCRUMPEL looks good. Are you planning to release the source code? Or at least a source for the 68HC11 version of it?

Peace and blessings,


  Are you sure? yes | no

Nick Brok wrote 02/17/2021 at 05:01 point

The Forth I made it originally for my 68HC11 from scratch. I ported it for 6809 which was not to difficult. I use the Grand Saerle BASIC . I have the BASIC in ROM plus my Scrumpelmonitor ported from the 68HC11. The Forth runs from $0100 and I load it with my monitor into memory.

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Thomas wrote 02/16/2021 at 21:33 point

Nice project :-)

Did you make your Forth from scratch?

Which legacy system was the source for the BASIC?

How do you deal with persistence of programs, both in Forth and in BASIC?   

  Are you sure? yes | no

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