mc9s08jm60 Freescale Semiconductor, Inc, mc9s08jm60 Datasheet - Page 38

• Manufacturer Part Number: mc9s08jm60
• Description: Hcs08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Chapter 3 Modes of Operation
3.6.1.2
Entry into the active background mode from run mode is enabled if ENBDM in BDCSCR is set. This
register is described in
STOP instruction, the system clocks to the background debug logic remain active when the MCU enters
stop mode. Because of this, background debug communication remains possible. In addition, the voltage
regulator does not enter its low-power standby state but maintains full internal regulation. If the user
attempts to enter stop2 with ENBDM set, the MCU will enter stop3 instead.
Most background commands are not available in stop mode. The memory-access-with-status commands
do not allow memory access, but they report an error indicating that the MCU is in stop or wait mode. The
BACKGROUND command can be used to wake the MCU from stop and enter active background mode
if the ENBDM bit is set. After entering background debug mode, all background commands are available.
3.6.2
Stop2 mode is entered by executing a STOP instruction under the conditions as shown in
of the internal circuitry of the MCU is powered off in stop2, with the exception of the RAM. Upon entering
stop2, all I/O pin control signals are latched so that the pins retain their states during stop2.
Exit from stop2 is performed by asserting either wake-up pin: RESET or IRQ/TPMCLK.
In addition, the RTC interrupt can wake the MCU from stop2, if enabled.
Upon wake-up from stop2 mode, the MCU starts up as from a power-on reset (POR):
In addition to the above, upon waking up from stop2, the PPDF bit in SPMSC2 is set. This flag is used to
direct user code to go to a stop2 recovery routine. PPDF remains set and the I/O pin states remain latched
until a 1 is written to PPDACK in SPMSC2.
To maintain I/O states for pins that were configured as general-purpose I/O before entering stop2, the user
must restore the contents of the I/O port registers, which have been saved in RAM, to the port registers
before writing to the PPDACK bit. If the port registers are not restored from RAM before writing to
PPDACK, then the pins will switch to their reset states when PPDACK is written.
For pins that were configured as peripheral I/O, the user must reconfigure the peripheral module that
interfaces to the pin before writing to the PPDACK bit. If the peripheral module is not enabled before
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All module control and status registers are reset
The LVD reset function is enabled and the MCU remains in the reset state if V
trip point (low trip point selected due to POR)
The CPU takes the reset vector
Stop2 Mode
Active BDM Enabled in Stop Mode
IRQ/TPMCLK always functions as an active-low wakeup input when the
MCU is in stop2, regardless of how the pin is configured before entering
stop2. It must be configured as an input before executing a STOP instruction
to avoid an immediate exit from stop2. This pin must be driven or pulled
high externally while in stop2 mode.
Chapter 18, “Development
MC9S08JM60 Series Data Sheet, Rev. 2
NOTE
Support.” If ENBDM is set when the CPU executes a
Freescale Semiconductor
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is below the LVD
Table
3-1. Most