AT89C55WD View Datasheet(PDF) - Atmel Corporation
Part Name
Description
MFG CO.
'AT89C55WD' PDF : 35 Pages View PDF
Table 21-1. Flash Programming Modes
Mode
Write Code
Data
Read Code
Data
Write Lock Bit
1
Write Lock Bit
2
Write Lock Bit
3
ALE/
VCC RST PSEN PROG
(1)
5V
H
L
EA/
VPP
12V
P2.6 P2.7 P3.3 P3.6 P3.7
L
H
H
H
H
5V
H
L
6.5
V
H
L
6.5
V
H
L
6.5
V
H
L
H
H/12V
L
L
L
H
H
(2)
12V
H
H
H
H
H
(2)
12V
H
H
H
L
L
(2)
12V
H
L
H
H
L
Read Lock Bits
5V
H
L
H
1, 2, 3
H
H
H
L
H
L
Chip Erase
6.5
V
H
L
(3)
12V
H
L
H
L
L
Read Atmel ID 5V
H
L
H
H
L
L
L
L
L
Read Device
ID
5V
H
L
H
H
L
L
L
L
L
Read Device
ID
5V
H
L
H
H
L
L
L
L
L
Notes:
1. Write Code Data requires a 200 ns PROG pulse.
2. Write Lock Bits requires a 100 µs PROG pulse.
3. Chip Erase requires a 200 ns - 500 ns PROG pulse.
4. RDY/BSY signal is output on P3.0 during programming.
P0.7-0
Data
DIN
DOUT
X
X
X
P0.2,
P0.3,
P0.4
X
1EH
55H
06H
P3.4
A14
P2.5-0
Address
P1.7-0
A13-8
A7-0
A14
A13-8
A7-0
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
XX 0000 00H
X
XX 0001 00H
X
XX 0010 00H
22 AT89C55WD
1921C–MICRO–3/05
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