SLE4442 Siemens, SLE4442 Datasheet - Page 21
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SLE4442
Manufacturer Part Number
SLE4442
Description
(SLE4432 / SLE4442) 256 Byte EEPROM
Manufacturer
Siemens
Datasheet
1.SLE4442.pdf
(35 pages)
2.3.5 Read Security Memory (SLE 4442 only)
Similar to the read command for the protection memory this command reads out the 4 bytes of the
security memory. The number of clock pulses during the outgoing data mode is 32. I/O is switched
to high impedance Z by an additional pulse. Without a preceeding successful verification of the PSC
the output of the reference bytes is suppressed, that means I/O outputs state L for the reference
data bytes.
Address
(decimal)
255
32
31
3
2
1
0
Command: READ SECURITY MEMORY
Binary
Hexadecimal
Figure 9
Read Security Memory
Semiconductor Group
:
:
Main Memory
Data Byte 255 (D7 … D0) –
:
Data Byte 32 (D7 … D0)
Data Byte 31 (D7 … D0)
:
Data Byte 3 (D7 … D0)
Data Byte 2 (D7 … D0)
Data Byte 1 (D7 … D0)
Data Byte 0 (D7 … D0)
B7
0
B6
0
B5
1
B4
1
Control
Protection Memory
–
–
Protection Bit 31 (D31) –
:
Protection Bit 3 (D3)
Protection Bit 2 (D2)
Protection Bit 1 (D1)
Protection Bit 0 (D0)
31
H
B3
0
19
B2
0
B1
0
Security Memory
(only SLE 4442)
–
–
–
–
Reference Data Byte 3(D7 … D0)
Reference Data Byte 2(D7 … D0)
Reference Data Byte 1(D7 … D0)
Error Counter
(0,0,0,0,0,D2,D1,D0)
B0
1
Address
A7…A0
No effect
No effect
Data
D7…D0
No effect
No effect
SLE 4432
SLE 4442