Rainbow Electronics AT89LS53 - Manual

AT89LS53
4-249
Features
• Compatible with MCS-51
™
Products
• 12K Bytes of In-System Reprogrammable Downloadable Flash Memory
- SPI Serial Interface for Program Downloading
- Endurance: 1,000 Write/Erase Cycles
• 2.7V to 6V Operating Range
• Fully Static Operation: 0 Hz to 12 MHz
• Three-Level Program Memory Lock
• 256 x 8 bit Internal RAM
• 32 Programmable I/O Lines
• Three 16-bit Timer/Counters
• Nine Interrupt Sources
• Programmable UART Serial Channel
• SPI Serial Interface
• Low Power Idle and Power Down Modes
• Interrupt Recovery From Power Down
• Programmable Watchdog Timer
• Dual Data Pointer
• Power Off Flag
Description
The AT89LS53 is a low-power, wide-voltage range, high-performance CMOS 8-bit
microcomputer with 12K bytes of downloadable Flash programmable and erasable
read only memory. The device is manufactured using Atmel’s high density nonvolatile
memory technology and is compatible with the industry standard 80C51 instruction
set and pinout. The on-chip downloadable Flash allows the program memory to be
reprogrammed in-system through an SPI serial interface or by a conventional nonvol-
atile memory programmer. By combining a versatile 8-bit CPU with downloadable
Flash on a monolithic chip, the Atmel AT89LS53 is a powerful microcomputer which
provides a highly flexible and cost effective solution to many embedded control appli-
cations.
The AT89LS53 provides the following standard features: 12K bytes of downloadable
Flash, 256 bytes of RAM, 32 I/O lines, programmable watchdog timer, two Data Point-
ers, three 16-bit timer/counters, a six-vector two-level interrupt architecture, a full
duplex serial port, on-chip oscillator, and clock circuitry. In addition, the AT89LS53 is
designed with static logic for operation down to zero frequency and supports two soft-
ware selectable power saving modes. The Idle Mode stops the CPU while allowing
the RAM, timer/counters, serial port, and interrupt system to continue functioning. The
Power Down Mode saves the RAM contents but freezes the oscillator, disabling all
other chip functions until the next interrupt or hardware reset.
The downloadable Flash can be changed a single byte at a time and is accessible
through the SPI serial interface. Holding RESET active forces the SPI bus into a serial
programming interface and allows the program memory to be written to or read from
unless Lock Bit 2 has been activated.
0851B-B–12/97
8-Bit
Microcontroller
with 12K Bytes
Flash
AT89LS53