AT89C55WD-24AU Atmel, AT89C55WD-24AU Datasheet - Page 23

• Manufacturer Part Number: AT89C55WD-24AU
• Description: IC 8051 MCU FLASH 20K 44TQFP
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C55WD-24AU

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 24MHz
• Connectivity: UART/USART
• Peripherals: WDT
• Number Of I /o: 32
• Program Memory Size: 20KB (20K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 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
• Processor Series: AT89x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: UART
• Maximum Clock Frequency: 33 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 4 V to 6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

1921D–MICRO–6/08
Figure 21-1. Programming the Flash Memory
Figure 21-2. Verifying the Flash Memory
Note:
*Programming address line A14 (P3.4) is not the same as the external memory address line A14
(P2.6).
3 - 33 MHz
3 - 33 MHz
PROGRAMMING
MODES TABLE
PROGRAMMING
MODES TABLE
SEE FLASH
0000H/4FFFH
0000H/4FFFH
SEE FLASH
ADDR.
ADDR.
A14*
A14*
A0 - A7
A0 - A7
A8 - A13
A8 - A13
P3.3
P1.0 - P1.7
P2.0 - P2.5
P3.4
P2.6
P2.7
P3.6
P3.7
XTAL2
XTAL1
GND
P1.0 - P1.7
P2.0 - P2.5
P3.4
P2.6
P2.7
P3.3
P3.6
P3.7
XTAL 2
XTAL1
GND
AT89C55WD
AT89C55WD
PSEN
PSEN
P3.0
RST
ALE
V
RST
ALE
EA
P0
V
CC
EA
P0
CC
4.5V to 5.5V
4.5V to 5.5V
PGM DATA
(USE 10K
PULL-UPS)
PGM
DATA
PROG
V /V
V
RDY/
BSY
V
IH
IH
V
IH
IH
PP
AT89C55WD
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