ZiLOG Z8 User Manual page 209

ZiLOG
STOP
STOP
STOP
Stop
STOP
Instruction Format:
Operation:
This instruction turns off the internal system clock (SCLK) and external crystal (XTAL) oscillation, and reduces
the standby current. The STOP mode is terminated by a RESET which causes the processor to restart the application
program at address 000CH.
Flags: C: Unaffected
Z: Unaffected
S: Unaffected
V: Unaffected
D: Unaffected
H: Unaffected
Note:
In order to enter STOP mode, it is necessary to first flush the instruction pipeline to avoid suspending execution in
mid-instruction. The user must execute a NOP immediately before the execution of the STOP instruction.
Example:
The statements:
place the Z8 into STOP mode.
UM001601-0803
NOP
STOP
Op Codes: FF 6F
Z8 Microcontrollers
Instruction Descriptions and Formats
12-69