GENERAL DESCRIPTION
The ST639x microcontrollers are members of the 8-bit HCMOS ST638x family, a series of devices specially orientedto TV applications.

■ 4.5 to 6V supply operating range
■ 8MHz Maximum Clock Frequency
■ User Program ROM: Up to 20140 bytes
■ Reserved Test ROM:Up to 340 bytes
■ Data ROM: User selectable size
■ Data RAM: 256 bytes
■ Data EEPROM: Up to 384 bytes
■ 42-Pin Shrink Dual in Line Plastic Package
■ Up to 23 software programmable general purpose Inputs/Outputs, including 2 direct LED driving Outputs
■ Two Timers each including an 8-bit counter with a 7-bit programmable prescaler
■ Digital Watchdog Function
■ Serial Peripheral Interface (SPI) supporting S-BUS/ I2C BUS and standard serial protocols
■ SPI for external frequency synthesis tuning
■ Up to Six 6-Bit PWM D/A Converters
■ AFC A/D converter with 0.5V resolution
■ Five interrupt vectors (IRIN/NMI, Timer 1 & 2, VSYNC, PWR INT.)
■ On-chip clock oscillator
■ 5 Lines by 15 Characters On-Screen Display Generator with 128 Characters
■ All ROM types are supported by pin-to-pin EPROM and OTP versions.
■ The development tool of the ST639x microcontrollers consists of the ST638x-EMU emulation and development system to be connected via a standard RS232 serial line to an MS-DOS Personal Computer.