MPC555
/
MPC556
QUEUED SERIAL MULTI-CHANNEL MODULE
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
14-65
Figure 14-17 Queue Transmit Software Flow
QTHE = 1?
Yes
No
Enable Queue Interrupt
Reset
Configure the Transmit Flow
QBHE = 1?
Yes
No
QTHEI = 1,
If Transmitting Greater
than 16 Data Frames,
Write QTSZ=n for First
Pass Use of the Queue
Set QTE and TE = 1
Enable Queue Interrupt
for First Use of the Queue.
If Finished Transmitting,
Then Clear QTE and/or TE
If Finished Transmitting,
Then Clear QTE and/or TE
DONE
DONE
Read Status Register with TC = 1,
Write SCTQ[0:n] (Clears TC)
Read Status Register with QTHE=1
Write QTHE = 0 (and QBHE if
Transmitting More than 8 Data
Must Have Equaled 16)
Read QTHE=1, Write QTHE=0
Write New Data SCTQ[0:7]
To Wrap, Write New QTSZ=n
Set QTWE (Previous QTSZ
If Transmitting Greater
Than 8 Data Frames on Wrap
Read QBHE=1,Write QBHE=0
Write New Data to SCTQ[8:15]
Frames)
QBHEI = 1
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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