Bram Jacobse

Tinkering CD Players & Digital Audio

Processors Masked Rom Dumps CD960 , CD94 ,CD 12

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Today I attempted to dump a the CPU mask_ROM’s s from a CD960, CD94, CD12.

  • Servo CPU : 80C51_F121
  • FTS CPU :80C51_F105
  • Feature CPU : 83C154_69 , in some service documantation also shown as  a 80C59

 

These players have some 8051 family processors with F-xxx masked ROMs. My first attempt is the Servo CPU version 80C51 F-121.

I found a nice little project on GitHub: 8051dumper

Recreated this project and got it working after some fiddling, took some time to find the External Clock_in problem

80c51 f121 dumped via the dumper and serial_USB in putty the data captured as Intel_Hex_File

And put the Data in a AT89C51RC Proof of Concept

Also dumped the Feature CPU 83HC154-69 and the FTS CPU 80C51-F105

Testing with copy