MC68HC05JJ6 Datasheet, PDF (76/216 Pages) Freescale Semiconductor, Inc – General Release Specification Microcontrollers

Operating Modes
6.4.3 Halt Mode
The STOP instruction puts the MCU in halt mode if selected by the stop
mask option. Halt mode is identical to wait mode, except that a variable
recovery delay occurs when the MCU exits halt mode. A recovery time
of from 1 to 16 or from 1 to 4064 internal bus cycles can be selected by
the oscillator startup delay mask option.
If the STOP instruction has been selected by the stop mask option to put
the MCU in halt mode, then the COP watchdog cannot be turned off
inadvertently by a STOP instruction.
6.4.4 Data-Retention Mode
In the data-retention mode, the MCU retains RAM contents and CPU
register contents at V_DD voltages as low as 2.0 Vdc. The data retention
feature allows the MCU to remain in a low-power consumption state
during which it retains data, but the CPU cannot execute instructions.
To put the MCU in the data retention mode:
1. Drive the RESET pin to a logic zero.
2. Lower the V_DD voltage. The RESET pin must remain low
continuously during data retention mode.
To take the MCU out of the data retention mode:
1. Return V_DD to normal operating voltage.
2. Return the RESET pin to a logic one.
General Release Specification
76
Operating Modes
MC68HC05JJ6/MC68HC05JP6 — Rev. 3.2
Freescale Semiconductor