[Coco] Some details on CoCo 1 ROM burning

Charles Hudson charles484 at twc.com
Sat Dec 18 07:36:33 EST 2021


As described earlier I have a CoCo 1 which came with Color Basic 1.1 in 
ROM and I am interested in fitting a TCDD controller and drive to the 
system.  Accordingly I need to upgrade the ROMs and add Extended Color 
Basic.

I have obtained MCM68766C35 EPROMs, blanked them, obtained a Needham's 
EMP-20 programmer and the DOS software, verified the parallel port 
operation of the EMP-20 with a '586 VLB machine and downloaded the CoCo 
ROM images from Tandy Color Computer Archive. I plan to use at least CB 
1.2 and ECB 11.  I know the ECB ROM goes in the higher-numbered IC slot, 
left if facing from the front.

Now I come to actually programming the EPROMs and two questions occur to 
me:  Which format are these ROM images?  Binary, Intel hex and Motorola 
S hex are possibilities (among others); I would assume Motorola hex 
format for these.  And should I load each ROM image with a 00 starting 
address in the ROM and let the hardware sort out the addressing?

Just checking...  Thanks for your replies.

-CH-



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