Semiconductor Group
10-11
1997-10-01
OTP Memory Operation
C541U
10.7
Access of Version Bytes
The C541U provides three version bytes at address locations FCH, FDH, and FEH. The information
stored in the version bytes, is defined by the mask of each microcontroller step, Therefore, the
version bytes can be read but not written. The three version bytes hold information as manufacturer
code, device type, and stepping code.
For reading of the version bytes the control lines must be used according table 10-2 and figure 10-
7. The address of the version byte must be applied at the port 1 address lines. PALE must not be
activated.
Figure 10-7
Read Version Byte(s) Waveform
Version bytes are typically used by programming systems for adapting the programming firmware
to specifc device characteristics such as OTP size etc.
Note: The 3 version bytes are implemented in a way that they can be also read during normal
program execution mode as a mapped register with bit RMAP in SFR SYSCON set. The
addresses of the version bytes in normal mode and programming mode are identical and
therefore they are located in the SFR address range.
The first step of the C541U will contain the following information at the version bytes :
Future steppings of the C541U will have a different version byte 2 (incremented value. version bytes
0 and 1 will remain unchanged for future steppings of the C541U.
Name
Address
Value
Version Byte 0
FCH
C5H
Version Byte 1
FDH
C1H
Version Byte 2
FEH
01H
MCT03422
PMSEL1,0
PALE
PROG
PRD
0,1
FC
FD
Port 2
Port 0
Ver. 2
FE
Ver. 1
Ver. 0
Summary of Contents for C541U
Page 1: ... 8 LW 026 0LFURFRQWUROOHU 8VHU V 0DQXDO http www siem ens d Sem iconductor ...
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Page 21: ...Semiconductor Group 2 6 1997 10 01 Fundamental Structure C541U ...
Page 37: ...Semiconductor Group 4 6 1997 10 01 External Bus Interface C541U ...
Page 133: ...Semiconductor Group 6 88 1999 04 01 On Chip Peripheral Components C541U ...
Page 163: ...Semiconductor Group 8 8 1997 10 01 Fail Safe Mechanisms C541U ...
Page 185: ...Semiconductor Group 10 14 1997 10 01 OTP Memory Operation C541U ...