AT89LV55-12AI Atmel, AT89LV55-12AI Datasheet - Page 19

• Manufacturer Part Number: AT89LV55-12AI
• Description: IC 8051 MCU FLASH 20K 44TQFP
• Manufacturer: Atmel
• Series: 89LVr

Specifications of AT89LV55-12AI

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 12MHz
• Connectivity: UART/USART
• 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): 2.7 V ~ 6 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: UART
• Maximum Clock Frequency: 12 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3 bit
• Operating Supply Voltage: 2.7 V to 6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -
• Peripherals: -
• Lead Free Status / Rohs Status: No

18. Programming Interface
Table 18-1.
Note:
0811E–MICRO–9/08
Mode
Write Code Data
Read Code Data
Write Lock
Chip Erase
Read Signature Byte
1. Chip Erase requires a 10 ms PROG pulse.
Flash Programming Modes
Bit-1
Bit-2
Bit-3
Every code byte in the Flash array can be written, and the entire array can be erased, by using
the appropriate combination of control signals. The write operation cycle is self-timed and once
initiated, will automatically time itself to completion.
All major programming vendors offer worldwide support for the Atmel microcontroller series.
Please contact your local programming vendor for the appropriate software revision.
Figure 18-1. Verifying the Flash Memory
RST
H
H
H
H
H
H
H
PSEN
L
L
L
L
L
L
L
PROGRAMMING
MODES TABLE
3-12 MHz
SEE FLASH
0000H/4FFFH
ADDR.
ALE/PROG
H
H
A14*
A8 - A13
A0 - A7
P1.0 - P1.7
P2.0 - P2.5
P2.6
P2.7
P3.6
P3.7
XTAL2
XTAL1
GND
P3.0
EA/V
AT89LV55
12V
12V
12V
12V
12V
H
H
PP
PSEN
RST
ALE
V
EA
P0
CC
P2.6
H
H
H
H
L
L
L
+5V
PGM DATA
(USE 10K
PULLUPS)
P2.7
V
V
H
H
H
L
L
L
L
I H
I H
AT89LV55
P3.6
H
H
H
H
L
L
L
P3.7
H
H
H
L
L
L
L
19