mc68hc705c4acfn Freescale Semiconductor, Inc, mc68hc705c4acfn Datasheet - Page 69

• Manufacturer Part Number: mc68hc705c4acfn
• Description: M68hc05 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

6.3.1 SCI During Stop Mode
6.3.2 SPI During Stop Mode
MC68HC705C4A • MC68HSC705C4A — Rev. 3.0
MOTOROLA
NOTE:
When the MCU enters stop mode, the baud rate generator stops, halting
all SCI activity. If the STOP instruction is executed during a transmitter
transfer, that transfer is halted. If a low input to the IRQ pin is used to exit
stop mode, the transfer resumes.
If the SCI receiver is receiving data and stop mode is entered, received
data sampling stops because the baud rate generator stops, and all
subsequent data is lost. Therefore, all SCI transfers should be in the idle
state when the STOP instruction is executed.
When the MCU enters the stop mode, the baud rate generator stops,
terminating all master mode SPI operations. If the STOP instruction is
executed during an SPI transfer, that transfer halts until the MCU exits
the stop mode by a low signal on the IRQ pin. If reset is used to exit stop
mode, the SPI control and status bits are cleared, and the SPI is
disabled.
If the MCU is in slave mode when the STOP instruction is executed, the
slave SPI continues to operate and can still accept data and clock
information in addition to transmitting its own data back to a master
device. At the end of a possible transmission with a slave SPI in stop
mode, no flags are set until a low on the IRQ pin wakes up the MCU.
Although a slave SPI in stop mode can exchange data with a master SPI,
the status bits of a slave SPI are inactive in stop mode.
Low-Power Modes
Low-Power Modes
Technical Data
Stop Mode
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