Features 80C52 Compatible 8051 Instruction Compatible Six 8-bit I/O Ports (64 pins or 68 Pins Versions) Four 8-bit I/O Ports (44 Pins Version) Three 16-bit Timer/Counters 256 bytes Scratch Pad RAM 10 Interrupt Sources With 4 Priority Levels ISP (In-System Programming) Using Standard V Power Supply CC Integrated Power Monitor (POR/PFD) to Supervise Internal Power Supply Boot ROM Contains Low Level Flash Programming Routines and a Default Serial 8-bit Flash Loader High-speed Architecture Microcontroller In Standard Mode: 40 MHz (Vcc 2.7V to 5.5V, Both Internal and External Code Execution) 60 MHz (Vcc 4.5V to 5.5V and Internal Code Execution Only) In X2 Mode (6 Clocks/Machine Cycle) AT89C51ID2 20 MHz (Vcc 2.7V to 5.5V, Both Internal and External Code Execution) 30 MHz (Vcc 4.5V to 5.5V and Internal Code Execution Only) 64K bytes On-chip Flash Program/Data Memory Byte and Page (128 bytes) Erase and Write 100k Write Cycles On-chip 1792 bytes Expanded RAM (XRAM) Software Selectable Size (0, 256, 512, 768, 1024, 1792 bytes) 768 bytes Selected at Reset for T89C51RD2 Compatibility On-chip 2048 bytes EEPROM block for Data Storage 100k Write Cycles Dual Data Pointer 32 KHz Crystal Oscillator Variable Length MOVX for Slow RAM/Peripherals Improved X2 Mode with Independant Selection for CPU and Each Peripheral Keyboard Interrupt Interface on Port 1 SPI Interface (Master/Slave Mode) 8-bit Clock Prescaler Two Wire Interface 400K bit/s Programmable Counter Array with: High Speed Output Compare/Capture Pulse Width Modulator Watchdog Timer Capabilities Asynchronous Port Reset Full Duplex Enhanced UART with Dedicated Internal Baud Rate Generator Low EMI (inhibit ALE) Hardware Watchdog Timer (One-time Enabled with Reset-Out), Power-Off Flag Power Control Modes: Idle Mode, Power-down Mode Power Supply: 2.7V to 5.5V Temperature Ranges: Industrial (-40 to +85C) Packages: PLCC44, VQFP44 Description AT89C51ID2 is a high performance CMOS Flash version of the 80C51 CMOS single chip 8-bit microcontroller. It contains a 64 Kbytes Flash memory block for program and for data. The 64 Kbytes Flash memory can be programmed either in parallel mode or in serial mode with the ISP capability or with software. The programming voltage is internally 4289C805111/05 generated from the standard V pin. CC 1The AT89C51ID2 retains all features of the Atmel 80C52 with 256 bytes of internal RAM, a 10-source 4-level interrupt controller and three timer/counters. In addition, the AT89C51ID2 has a Programmable Counter Array, an XRAM of 1792 bytes, a Hardware Watchdog Timer, SPI and Keyboard, a more versatile serial channel that facilitates multiprocessor communication (EUART) and a speed improvement mechanism (X2 mode). The fully static design of the AT89C51ID2 allows to reduce system power consumption by bringing the clock frequency down to any value, even DC, without loss of data. The AT89C51ID2 has 2 software-selectable modes of reduced activity and 8-bit clock prescaler for further reduction in power consumption. In the Idle mode the CPU is frozen while the peripherals and the interrupt system are still operating. In the power-down mode the RAM is saved and all other functions are inoperative. The added features of the AT89C51ID2 make it more powerful for applications that need pulse width modulation, high speed I/O and counting capabilities such as alarms, motor control, corded phones, smart card readers. Table 1. Memory Size and I/O pins TOTAL RAM AT89C51ID2 Flash (bytes) XRAM (bytes) (bytes) I/O PLCC44/VQFP44 64K 1792 2048 34 2 AT89C51ID2 4289C805111/05