Designed by Mark Little
The AT90S4434/8535 is a low-power CMOS 8-bit microcontroller based on the AVR® enhanced RISC architecture. By executing powerful instructions in a single clock cycle, the AT90S4434/8535 achieves throughputs approaching 1 MIPS per MHz allowing the system designer to optimize power consumption versus processing speed.
The AT90S8535 provides the following features:
• 8K bytes of In-System Programmable Flash, • 512 bytes EEPROM,
• 512 bytes SRAM, • 32 general purpose I/O lines,
• 32 general purpose working registers, • RTC,
• three flexible timer/counters with compare modes, • internal and external interrupts,
• a programmable serial UART, • 8-channel, 10-bit ADC,
• programmable Watchdog Timer with internal oscillator, • an SPI serial port and
• three software selectable power saving modes.
AT90S8535 projects use the Hot Chip microprocessor board, marketed by Dick Smith Electronics around 1999 (when it was still an electronics company. It was marketed with a BASIC compiler and communicated via an RS232 serial port. That compiler is no longer compatible with modern Windows operating systems and has been replaced with the MikroElectronika mikroBasic PRO for AVR Version 7.0.1. A free version of the compiler with limitations on program size is available. If you are looking for something more low level, there are public domain AVR macro assemblers suitable for the AT90S8535.