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CC-40 Operating System Source Code.


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Nope.

 

There was a 32K bank switched ROM (8Kx4) as well as the CPU ROM (the CC-40 is the upper 2K of memory space, the Cc-40+ and TI-74 were upper 4K of memory space).  The CC-40+ and TI-74 both had extra cassette routines added to the CPU ROM, thus the extra 2K.  (Side note:  It'd be interesting to compare the CPU ROM of the CC-40 and TI-74 - Ksarul still needs to dump the CC-40+ Processor ROM).

 

So, you'd have to disassemble and comment 32K + 2K - that's quite a bit :)

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19 hours ago, acadiel said:

Nope.

 

There was a 32K bank switched ROM (8Kx4) as well as the CPU ROM (the CC-40 is the upper 2K of memory space, the Cc-40+ and TI-74 were upper 4K of memory space).  The CC-40+ and TI-74 both had extra cassette routines added to the CPU ROM, thus the extra 2K.  (Side note:  It'd be interesting to compare the CPU ROM of the CC-40 and TI-74 - Ksarul still needs to dump the CC-40+ Processor ROM).

 

So, you'd have to disassemble and comment 32K + 2K - that's quite a bit :)

 

For others following along, we do have a lot of good documentation in the CC-40 Editor Assembler manual here:

http://ftp.whtech.com/hexbus_cc40_ti74/CC40 Editor-Assembler/

 

Here are a few facts from chapter 6:

0000-007F  Register File (R0 is a byte at 0000, R127 is at 007F)
0080-00FF  Unused
0100-01FF  Peripheral File (Memory Mapped Devices) P0 to P127
0200-07FF  Unused
0800-0FFF  Built in 2K RAM
1000-4FFF  Built-in RAM, up to 16K (Cartridge RAM can be paged on top of this)
5000-CFFF  Cartridge ROM or RAM up to 16K
D000-EFFF  System ROM (8K pages from 32K total)
F000-F7FF  Unused
F800-FFFF  Processor ROM (onboard TMS70C20)


Examples of Peripheral "File" registers:

>104 is a read byte from keyboard rows
>106 is the keyboard col selector
>11E and >11F interface to the LCD display
>119 System ROM bank# (2 bits) and cartridge bank# (2 bits)

Addresses D000-EFFF would be the OS in 8K pages. Routines are documented in the manual.

 

The 2K of processor ROM is the "BIOS" which initializes the system and enables all the memory banks.

 

The manual is unclear about the differences in paging the two cartridge memory areas.

 

Pages 6-15 and 6-16 are missing, presumably saying more about interrupts and the timer.

 

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10 hours ago, FarmerPotato said:

 

For others following along, we do have a lot of good documentation in the CC-40 Editor Assembler manual here:

http://ftp.whtech.com/hexbus_cc40_ti74/CC40 Editor-Assembler/

 

Pages 6-15 and 6-16 are missing, presumably saying more about interrupts and the timer.

 

 

 

http://ftp.whtech.com/hexbus_cc40_ti74/CC40 Editor-Assembler/CC40 EA Reference chapt 4-6.pdf

6-15 and 6-16 come after 6-18 for some reason (6-17, 6-18, 6-15, 6-16, 6-19)

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