AT80C51RD2-RLTIM Atmel, AT80C51RD2-RLTIM Datasheet - Page 2

• Manufacturer Part Number: AT80C51RD2-RLTIM
• Description: IC MCU 8051 5V SPI 20MHZ 44-VQFP
• Manufacturer: Atmel
• Series: 80Cr

Specifications of AT80C51RD2-RLTIM

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Type: ROMless
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Program Memory Size: -
• Data Converters: -

1. Description
2. Block Diagram
2
AT80C51RD2
ALE/
XTAL1
XTAL2
PSEN
PROG
WR
RD
EA
AT80C51RD2 microcontrollers are high performance versions of the 80C51 8-bit
microcontrollers.
The microcontrollers retain all features of the Atmel 80C52 with 256 bytes of internal RAM, a 7-
source 4-level interrupt controller and three timer/counters.
In addition, the microcontrollers have a Programmable Counter Array, an XRAM of 1024 byte, a
Hardware Watchdog Timer, a Keyboard Interface, a more versatile serial channel that facilitates
multiprocessor communication (EUART) and a speed improvement mechanism (X2 mode).
The microcontrollers have 2 software-selectable modes of reduced activity and 8 bit clock pres-
caler for further reduction in power consumption. In 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.
Table 1. Memory Size
Notes:
(2)
(2)
AT80C51RD2
CPU
1. Alternate function of Port 1
2. Alternate function of Port 3
(2) (2)
(2)
Timer 0
Timer 1
EUART
BRG
(2)
+
CORE
C51
(2) (2)
256x8
RAM
INT
Ctrl
ROM (Bytes)
ROMless
IB-bus
Parallel I/O Ports & Ext. Bus
Port 0Port 1 Port 2 Port 3
XRAM
1Kx8
XRAM (Bytes)
(1)
1024
PCA
(1)
(1)
Watch
Dog
Timer2
(1)
TOTAL RAM (Bytes)
Board
Key
1280
4113D–8051–01/09
I/O
32