AT89C51RD2-SLRUM Atmel, AT89C51RD2-SLRUM Datasheet - Page 13

• Manufacturer Part Number: AT89C51RD2-SLRUM
• Description: IC MCU FLASH 8051 EEP 64K 44PLCC
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C51RD2-SLRUM

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 60MHz
• Connectivity: SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 34
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-PLCC
• For Use With: AT89OCD-01 - USB EMULATOR FOR AT8XC51 MCUAT89STK-11 - KIT STARTER FOR AT89C51RX2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Compliant
• Other names: AT89C51RD2-SLRUMTR

Table 4-1.
4235K–8051–05/08
ALE/PRO
G
PSEN
EA
Mnemonic
Pin Description (Continued)
PLCC44 VQFP44
33
32
35
27
26
29
Pin Number
PLCC68
68
67
2
VQFP64
56
55
58
Type
O (I)
O
I
Name and Function
Address Latch Enable/Program Pulse: Output pulse for latching the
low byte of the address during an access to external memory. In normal
operation, ALE is emitted at a constant rate of 1/6 (1/3 in X2 mode) the
oscillator frequency, and can be used for external timing or clocking. Note
that one ALE pulse is skipped during each access to external data
memory. This pin is also the program pulse input (PROG) during Flash
programming. ALE can be disabled by setting SFR’s AUXR.0 bit. With
this bit set, ALE will be inactive during internal fetches.
Program Strobe ENable: The read strobe to external program memory.
When executing code from the external program memory, PSEN is
activated twice each machine cycle, except that two PSEN activations
are skipped during each access to external data memory. PSEN is not
activated during fetches from internal program memory.
External Access Enable: EA must be externally held low to enable the
device to fetch code from external program memory locations 0000H to
FFFFH. If security level 1 is programmed, EA will be internally latched on
Reset.
AT89C51RD2/ED2
13