GENERAL DESCRIPTION
The XA-S3 device is a member of Philips Semiconductors’ XA (eXtended Architecture) family of high performance 16-bit single-chip microcontrollers.
The XA-S3 device combines many powerful peripherals on one
chip. With its high performance A/D converter, timers/counters, watchdog, Programmable Counter Array (PCA), I2C interface, dual UARTs, and multiple general purpose I/O ports, it is suited for general multipurpose high performance embedded control functions.

Specific features of the XA-S3
• 2.7 V to 5.5 V operation.
• 32 K bytes of on-chip EPROM/ROM program memory.
• 1024 bytes of on-chip data RAM.
• Supports off-chip addressing up to 16 megabytes (24 address
   lines). A clock output reference is added to simplify external bus
   interfacing.
• High performance 8-channel 8-bit A/D converter with automatic
   channel scan and repeated read functions. Completes a
   conversion in 4.46 microseconds at 30 MHz. Alternate operating
   mode allows 10-bit conversion results.
• Three standard counter/timers with enhanced features. All timers
   have a toggle output capability.
• Watchdog timer.
• 5-channel 16-bit Programmable Counter Array (PCA).
• I2C-bus serial I/O port with byte-oriented master and slave functions.
• Two enhanced UARTs with independent baud rates.
• Seven software interrupts.
• Active low reset output pin indicates all reset occurrences
   (external reset, watchdog reset and the RESET instruction). A
   reset source register allows program determination of the cause of
   the most recent reset.
• 50 I/O pins, each with 4 programmable output configurations.
• 30 MHz operating frequency at 2.7–5.5 V VDD.
• Power saving operating modes: Idle and Power-down. Wake-up
   from power-down via an external interrupt is supported.
• 68-pin PLCC and 80-pin PQFP packages.