KXT11-A2 1K Firmware for the SBC-11/21
Overview
I have made the KXT11-A2 firmware for the SBC-11/21 Falcon single board computer available in source code and binary format. A ZIP file can be downloaded at the link below. It contains a MACRO-11 source file, the MACRO-11 listing, a new PDF listing, and binary images of the two ROMs. The source files were recreated from the listing in Appendix D of the Digital SBC-11/21 Single-Board Computer User’s Guide.
The files are provided “as-is”. No guarantees or warranties are made regarding the accuracy of any of the contents. The files included are copyrighted by their respective authors.
The new source file was assembled on a simulated PDP-11/03, running RT-11 V4.00C, then tested on an M8063-BA (Revision D) module. The functions that were tested and are known to work are as follows:
- ODT commands testing memory, registers, Go and Proceeed.
- “X” command, testing the auxiliary serial port and parallel port.
- TU58 tape boot using a TU58 emulator. XXDP was booted and the NKXAB0 11/21-KXT-11 CPU diagnostics were run on the module.
Items that were not tested are as follows:
- RX-01/RX-02 floppy boot.
- RT-11 standalone boot on the TU58.
Building the ROM Image
The process of building the ROM image involves assembling, linking, converting the output from the linker into a raw binary image, then finally splitting the image into high and low byte ROM images.
The steps are provided below. Comments are shown in red text. User input is shown in bold text.
- Obtain a copy of Bob Supnik’s simh computer simulator and install it.
- Create a folder to hold the virtual machine.
- Obtain a copy of RT-11 V4 from Bob's site and extract it in the new folder.
- Copy the FALCON.MAC file into the Disks folder.
- Start the PDP-11 simulator from the Disks folder.
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Type the following commands on the simulator's command line:
sim>ATTACH RK0 rtv4_rk.dsk <== Attaches the RT-11 disk image to drive RK0.
sim>ATTACH PTR FALCON.MAC <== Sets up the source file on the paper tape reader.
sim>ATTACH PTP FALCON.LDA <== Sets up the output file on the paper tape punch.
sim>BOOT RK0 <== Boots up RT-11.
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The simulator will boot RT-11 and a “.” prompt will appear.
Type in the following commands:
.COPY PC: FALCON.MAC <== Copies the source code from the paper tape reader to the disk.
Files copied:
PC: to DK:FALCON.MAC
.MACRO FALCON <== Assembles the source code.
ERRORS DETECTED: 0
.LINK /LDA FALCON <== Converts the object file to an LDA format file.
.COPY FALCON.LDA PC: <== Copies the output file to the paper tape punch.
Files copied:
DK:FALCON.LDA to PC:
.^E <== Ctrl-E suspends the simulator.
Simulation stopped, PC: 122124 (EMT 340)
sim> quit <== Quit the simulator.
Goodbye. -
The LDA file can be convered to a binary file using the program below.
The program is used as follows:
lda2bin -i FALCON.LDA -o FALCON.BIN
Most modern EPROM programmers can split the file into the low and high byte components for the KXT11 module.
References
- M8063 Falcon SBC-11/21 Single-Board Computer User's Guide, 2nd Preliminary, December 1981 (EK-KXT11-UG-PR1)
- SBC-11/21 Single-Board Computer User's Guide, 1st Edition, June 1982 (EK-SBC01-UG-001)
- RT-11 System User's Guide, RT-11 V4.0, March 1980 (AA-5279B-TC)
- RT-11 System Software Support Manual, RT-11 V4.0, March 1981 (AA-H379A-TC)
