ST9291

The ST9291 is a ROMmember of the ST9 family of microcontrollers, completely developed and produced by SGS-THOMSON Microelectronics using a proprietary n-well HCMOS process.

The ROM parts are fully compatible with their EPROMand OTP (One-Time Programmable) versions, which may be used for the prototyping and pre-production phases of development.

The nucleus of the ST9291 is the advanced ST9 Core which includes the Central Processing Unit (CPU), the Register File, a 16-bit Timer/Watchdog with 8-bit Prescaler, a Serial Peripheral Interface supporting S-bus, I2C-bus and IM-bus Interface, plus two 8-bit I/O ports. The Core has independent memory and register buses allowing a high degree of pipelining to add to the efficiency of the code execution speed of the extensive instruction set.

The powerful I/O capabilities demanded by microcontroller applications are fulfilled by the ST9291 with up to 32/42 I/O lines dedicated to digital Input/ Output. These lines are grouped into up to six I/OPorts and can be configured on a bit basis under software control to provide timing, status signals, timer inputs and outputs, analog inputs, external interrupts, OSD (On Screen Display) output and serial or parallel I/O.

Three basic memory spaces of the ST9291 are available to support  this wide range of configurations: Program Memory, Data Memory and the Register File, which includes the control and status registers of the on-chip peripherals.

The human interface of the ST9291 is provided by the On Screen Display module, this can produce up to 15 lines of up to 34 characters from a ROMdefined 128 character set. The 9x13 character can be modified by 4 different pixel sizes, with character rounding, and formed into words with colour and format attributes. A 14-bit VS (Voltage Synthesis) output using the PWM (Pulse Width Modulation)/BRM (Bit Rate Modulation) of the ST9291 is present to generate tuning voltages for low-mid range TV set applications. The tuning voltage is output on one of two separate output pins.

A 16-bit Slice Timer with an 8-bit Prescaler is also present.