The M37212M6-XXXSP/FP, M37212M4/M8-XXXSP are single-chip microcomputers designed with CMOS silicon gate technology. They have a OSD, I2C-BUS interface, and PWM, so it is useful for a channel selection system for TV. The feature of the M37212EFSP/FP are similar to those of the M37212M6-XXXSP/FP except that these chips have a built-in PROM which can be written electrically. The differences between the M37212M6-XXXSP/FP and M37212M4/M8-XXXSP are the ROM size and the RAM size as shown below. Accordingly, the following descriptions will be for M37212M6-XXXSP/FP unless otherwise noted.