MPC555
/
MPC556
QUEUED SERIAL MULTI-CHANNEL MODULE
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
14-32
Figure 14-11 Flowchart of QSPI Slave Operation (Part 2)
Normally, the SPI bus performs synchronous bi-directional transfers. The serial clock
on the SPI bus master supplies the clock signal SCK to time the transfer of data. Four
Set SPIF
Status Flag
Request Interrupt
Is Interrupt
Enable Bit
SPIFIE Set?
Is Wrap
Enable Bit
Asserted?
Y
N
Reset Working Queue
Pointer To NEWQP or 0x0000
Y
Disable QSPI
A2
N
Increment Working
Queue Pointer
N
Is HALT
or FREEZE
Asserted?
A2
Halt QSPI and
Set HALTA
N
Is Interrupt
Enable Bit
HMIE Set?
Y
Y
N
Is HALT
Or FREEZE
Asserted?
C2
Y
N
Y
Is this the
Last Command
in the Queue?
QSPI SLV2 FLOW6
Request Interrupt
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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