MPC555
/
MPC556
QUEUED SERIAL MULTI-CHANNEL MODULE
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
14-73
14.9.12 Example QSCI1 Receive Operation of 17 Data Frames
shows an example receive operation of 17 data frames. The bold type
indicates the current value for the QRPNT. Action of the queue may be followed by
starting at the top of the figure and going left to right and then down the page.
Figure 14-23 Queue Receive Example for 17 Data Bytes
0000
0111
1000
1111
QRPNT
SCRQ[0]
SCRQ[7]
SCRQ[8]
SCRQ[15]
0000
0111
1000
1111
QRPNT
SCRQ[0]
SCRQ[7]
SCRQ[8]
SCRQ[15]
Read SCSR and SCRQ[0:7]
Clear QTHF
0000
0111
1000
1111
QRPNT
SCRQ[0]
SCRQ[7]
SCRQ[8]
0000
0111
1000
1111
QRPNT
SCRQ[0]
SCRQ[7]
0001
Data
Available
Received
Space
QTHF Interrupt Received
SCRQ[15]
Read SCRQ[8:15]
Clear QBHF
QBHF Interrupt Received
SCRQ[8]
SCRQ[15]
Clear QRE/RE
Receive Queue Enabled
Read SCRQ[0]
IDLE Interrupt Received
1
2
3
4
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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