GENERAL DESCRIPTION
The ST90158 and ST90135 microcontrollers are developed and manufactured by STMicroelectronics using a proprietary n-well CMOS process. Their performance derives from the use of a flexible 256-register programming model for ultra-fast context switching and real-time event response. The intelligent on-chip peripherals offload the ST9 core from I/O and data management processing tasks allowing critical application tasks to get the maximum use of core resources. The new-generation ST9 MCU devices now also support low power consumption and low voltage operation for power-efficient and low-cost embedded systems.

■ Register File based 8/16 bit Core Architecture with RUN, WFI, SLOW and HALT modes
■ 0 - 16 MHz Operation @ 5V±10%, -40°C to +85°C and 0°C to +70°C Operating Temperature Ranges
■ 0 - 14 MHz Operation @ 3V±10% and 0°C to +70°C Operating Temperature Range
■ Fully Programmable PLL Clock Generator, with Frequency Multiplication and low frequency, low cost external crystal
■ Minimum 8-bit Instruction Cycle time: 83ns - (@24 MHz internal clock frequency)
■ Minimum 16-bit Instruction Cycle time: 250ns -(@ 24 MHz internal clock frequency)
■ Internal Memory:
– EPROM/OTP/ROM 16/24/32/48/64K bytes
– ROMless version available
– RAM 512/768/1K/1.5K/2K bytes
■ Maximum External Memory: 64K bytes
■ 224 general purpose registers available as RAM, accumulators or index pointers (register file)
■ 80-pin Plastic Quad Flat Package and 80-pin Thin Quad Flat Package
■ 67 fully programmable I/O bits
■ 8 external and 1 Non-Maskable Interrupts
■ DMA Controller and Programmable Interrupt Handler
■ Single Master Serial Peripheral Interface
■ Two 16-bit Timers with 8-bit Prescaler, one usable as a Watchdog Timer (software and hardware)
■ Three (ST90158) or two (ST90135) 16-bit Multifunction Timers, each with an 8 bit prescaler, 12 operating modes and DMA capabilities
■ 8 channel 8-bit Analog to Digital Converter, with Automatic voltage monitoring capabilities and external reference inputs
■ Two (ST90158) or one (ST90135) Serial Communication Interfaces with asynchronous, synchronous and DMA capabilities
■ Rich Instruction Set with 14 Addressing modes
■ Division-by-Zero trap generation