0.1G/0.2M (rev_3)
   First release for beta boards

0.3G/0.4M (rev_3)
   Temp fix for 0.1G flashing bug on beta boards

0.7G/0.8M (rev_3)
   Fixed intermittent black and white PAL boot issue
   Fixed EEPROM magic read issue at boot
   Fixed FLASH bulk read/write issue
   Moved CAS out by ~15ns for better timing on some boards.
   Changed CAS/RAS/AEC/PHI/BA to SLOW skew
   Changed CAS/RAS/AEC/PHI/BA to 4ma drive
   Changed CAS to always pulse low even on refresh (for beamracer compat)
   Added white line to composite on first visible horizontal pixel
   Fixed signed division result register error
   Fixed division by zero flag on math module
   Fixed incompatibilty issue for register sets with beamracer

1.4/1.5 (rev_4H, rev_4G, rev_4L, rev_3)
   Added blitter and math regs

1.8 (rev_4L, rev_4G)
   Fixed timing issue for NTSC analog RGB signals causing B/W pic
