The source code of the CBIOS for the Televideo TS-802, one of the many CP/M business computers released in the early 1980s. Each revision of the CBIOS should contain these files:
802HBIOS.MAC - (Includes all MAC files except 802HBOOT.MAC)
802HBASE.MAC - (BIOS main routine)
802HCONS.MAC - (BIOS console and printer driver)
802HHARD.MAC - (BIOS hard disk driver)
802HFLOP.MAC - (BIOS floppy disk driver)
802HBOOT.MAC - (BIOS boot program)
CPM59.COM - (BDOS and CCP routine)
MAKESYS.COM - (Writes CP/M to the system track)
You will also need Microsoft Macro-80 to compile the code, which I provided in the repository.
Here's the entireity of Appendix O lifted straight from the Installation and User's guide of the machine.
To modify CBIOS, you must have:
The diskette labeled CBIOS (included with the TS B02), which contains the following files:
802FBIOS.MAC 802FBOOT.MAC 802FCONS.MAC 802FDISK.MAC
802FSUBS.MAC 802FEQU.MAC 802DATA.MAC MAKESYS.COM
CPM62.COM 802FBOOT.COM
A second diskette containing M8O.COM, L8O.COM, CREF8O.COM (or equivalents), and an editor.
The procedure used to modify the CBIOS is as follows:
- Insert the diskette labeled CBIOS in Drive B.
- Insert the diskette containing M8O in Drive A
- Set the default drive to B: by typing B:.
- Modify CBIOS source modules on the diskette in Drive B using an editor of your choice.
- Assemble 802FBIOS.MAC using the M8O assembler, as follows:
B)A:M80 = 802FBIOS/C
This will create two files:
B:802FBIOS.REL
B:802FBIOS.CRF
- Run CREF8O as follows:
A)A:CREF80 = 802FBIOS
This will create a cross reference listing in file B:B02FBIOS.PRN.
- Link 802FBIOS.REL using L8O as follows:
A)A:L80/P:100, 802FBIOS/N,802FBIOS/E
This creates the file B:802FBIOS.COM, which contains your modifications to CBIOS.
Now you are ready to build a new user CP/M diskette which will incorporate your modifications.
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Insert the diskette which will contain the new system into Drive A.
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Run MAKESYS as follows:
B)MAKESYS
Destination Drive? A
Bootstrap Filename? 802FBOOT
BDOS Filename? CPM59
BIOS Filename? 802FBIOS
MAKESYS COMPLETED
The new system is now on the diskette in Drive A Reset the system and run it.
Note: These instructions may differ a little depending on which revision of the CBIOS you decide to compile, so keep that in mind.