SAF-C164SM Infineon Technologies, SAF-C164SM Datasheet - Page 419

• Manufacturer Part Number: SAF-C164SM
• Description: 16-Bit CMOS Microcontroller
• Manufacturer: Infineon Technologies

The following registers are secured by the described unlock sequence:
Table 21-7
Register Name
SYSCON1
SYSCON2
SYSCON3
RSTCON
Code Examples
The code examples below show how the unlock sequence is used to access register
SYSCON2 (marked *!* in the comment column) in an application in order to change the
basic clock generation mode.
Examples where the PLL keeps running:
;________________________;______________________________________
ENTER_SLOWDOWN:
MOV
EXTR
BFLDL SYSCON2,#0FH,#09H
MOV
BSET
BFLDH SYSCON2,#03H,#01H ;CLKCON=01B --> SDD frequency, PLL on *!*
;________________________;______________________________________
EXIT_SLOWDOWN:
MOV
EXTR
BFLDL SYSCON2,#0FH,#09H
MOV
BSET
BFLDH SYSCON2,#03H,#00H ;CLKCON=00B --> basic frequency
User’s Manual
SYSCON2, ZEROS
#4H
SYSCON2,#0003H
SYSCON2.2
SYSCON2, ZEROS
#4H
SYSCON2,#0003H
SYSCON2.2
Special Registers Secured by the Unlock Sequence
Description
Controls sleep mode
Controls clock generation (SDD) and the unlock sequence itself
Controls the flexible peripheral management
Controls the configuration of the C164CM
(basic clock generation mode, CS lines, segment address width)
and the length of the reset sequence
;Currently running on basic clock frequ.
;Clear bits 3-0 (no EXTR required here)
;Switch to ESFR space and lock sequence
;Unlock sequence, step 1 (1001B)
;Unlock sequence, step 2 (0011B)
;Unlock sequence, step 3 (0111B)
;Single access to one locked register
;Currently running on SDD frequency
;Clear bits 3-0 (no EXTR required here)
;Switch to ESFR space and lock sequence
;Unlock sequence, step 1 (1001B)
;Unlock sequence, step 2 (0011B)
;Unlock sequence, step 3 (0111B)
;Single access to one locked register
21-23
Power Management
C164CM/C164SM
Derivatives
V1.0, 2002-02
*!*