3 to 6.0V Supply Operating Range
8 MHz Maximum Clock Frequency
-25 to +85°C Operating Temperature Range
Run, Wait & Stop Modes
■ 5 different interrupt vectors
■ Look-up table capability in ROM
User ROM:
■ Data ROM:
3868 bytes
User selectable size
(in program ROM)
128 bytes
128 bytes
Data RAM:
■ EEPROM:
■ PDIP28, PSO28 packages
■ 21 fully software programmable I/O as:
- Input with pull-up resistor
- Input without pull-up resistor
- Input with interrupt generation
-Open-drain or push-pull outputs
-Analog Inputs
8 I/O lines can sink up to 20mA for direct LED or
TRIAC driving
■ 8 bit counter with a 7-bit programmable prescaler
(Timer1)
. 8 bit auto-reload timer with 7-bit programmable
prescaler (AR Timer)
■ Digital Watchdog
■ 8 bit A/D Converter with up to 13 analog inputs
▪ 8 bit Synchronous Peripheral Interface (SPI)
■ On-chip clock oscillator (Quartz Crystal or Ce-
ramic)
■ Power-on Reset
■ Clock output
■9 powerful addressing modes
■ The development tool of the ST6294 microcon-
trollers consists of the ST626x-EMU emulation
and development system connected via a stand-
ard RS232 serial line to an MS-DOS Personal
Computer

GENERAL DESCRIPTION
The ST6294 microcontroller is member of the 8-bit
HCMOS ST62xx family, a series of devices oriented
to low-medium complexity applications. All ST62xx
members are based on a building block approach: a
common core is surrounded by a combination of on-
chip peripherals (macrocells).
The macrocells of the ST6294 are: the Timer pe-
ripheral that includes an 8-bit counter with a 7-bit
software programmable prescaler (Timer1), the 8-
bit Auto-reload Timer with 7 bit programmable
prescaler (AR Timer), the 8-bit A/D Converter with
up to 13 analog inputs (A/D inputs are alternate
functions of I/O pins), the Digital Watchdog (DWD)
and an 8-bit Serial synchronous Peripheral Inter-
face (SPI). In addition, these devices offer 128
bytes of EEPROM for non volatile data storage.
The ST6294 is a version of the ST6265 specifically
tailored to be used in telephone set applications.
The only difference is that a CKOUT pin is provided
instead of the NMI pin. For this reason this
datasheet only contains information relating to the
differences to the ST6265, and thus should be read
in conjunction with the ST6265 datasheet. The
ST62E94 EPROM version is available for prototypes
and low-volume production; also OTP version is
available.