Friday, October 14, 2011

frequency modifier

As I said in previous posts, the Custom SH2 is feeded with a 6.25Mhz clock. and then multiplied by a factor of 4.

According to SH2 specificactions, this should be done by writting a certain value (2 in this case to address H'FFFFFE90). This must be done from the cache memory (H'C0000000 area). Until this is done, the CPU runs at 6.25Mhz. This means that Flash rom is being read at a lower pace until we force the CPU to run faster.

Still waiting for the sygnal analyzer....

1 comment:

  1. Hey, great progress! Hoping you got the signal analyzer :)

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