INTRODUCTION
The ST72521(A)R and ST72521M devices are members of the ST7 microcontroller family designed for mid-range applications with a CAN bus interface (Controller Area Network). All devices are based on a common industry standard 8-bit core, featuring an enhanced instruction set and are available with FLASH or ROM program memory.

■ Memories
– 32K to 60K dual voltage High Density Flash (HDFlash) or ROM with read-out protection capability. In-Application Programming and In-Circuit Programming for HDFlash devices
– 1K to 2K RAM
– HDFlash endurance: 100 cycles, data retention: 20 years at 55°C
■ Clock, Reset And Supply Management
– Enhanced low voltage supervisor (LVD) for main supply and auxiliary voltage detector (AVD) with interrupt capability
– Clock sources: crystal/ceramic resonator oscillators, internal RC oscillator, clock security system and bypass for external clock
– PLL for 2x frequency multiplication
– Four power saving modes: Halt, Active-Halt, Wait and Slow
■ Interrupt Management
– Nested interrupt controller
– 14 interrupt vectors plus TRAP and RESET
– Top Level Interrupt (TLI) pin
– 15 external interrupt lines (on 4 vectors)
■ Up to 64 I/O Ports
– 48 multifunctional bidirectional I/O lines
– 34 alternate function lines
– 16 high sink outputs
■ 5 Timers
– Main Clock Controller with: Real time base, Beep and Clock-out capabilities
– Configurable watchdog timer
– Two 16-bit timers with: 2 input captures, 2 out put compares, external clock input on one timer, PWM and pulse generator modes
– 8-bit PWM Auto-Reload timer with: 2 input captures, 4 PWM outputs, output compare Device Summary and time base interrupt, external clock with event detector
■ 4 Communications Interfaces
– SPI synchronous serial interface
– SCI asynchronous serial interface (LIN compatible)
–I2C multimaster interface
– CAN interface (2.0B Passive)
■ Analog peripheral
– 10-bit ADC with 16 input pins
■ Instruction Set
– 8-bit Data Manipulation
– 63 Basic Instructions
– 17 main Addressing Modes
– 8 x 8 Unsigned Multiply Instruction
■ Development Tools
– Full hardware/software development package
– In-Circuit Testing capability