SLE4442 Siemens, SLE4442 Datasheet - Page 17

• Manufacturer Part Number: SLE4442
• Description: (SLE4432 / SLE4442) 256 Byte EEPROM
• Manufacturer: Siemens

2.3.2 Read Protection Memory (SLE 4432 and SLE 4442)
The command transfers the protection bits under a continuous input of 32 clock pulses to the output.
I/O is switched to high impedance Z by an additional pulse. The protection memory can always be
read, and indicates the data bytes of the main memory protected against changing.
Address
(decimal)
255
32
31
3
2
1
0
Command: READ PROTECTION MEMORY
Binary
Hexadecimal
Figure 6
Read Protection 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)
34
H
B3
0
15
B2
1
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
B0
0
Address
A7…A0
No effect
No effect
Data
D7…D0
No effect
No effect
SLE 4432
SLE 4442