MPC555
/
MPC556
QUEUED ANALOG-TO-DIGITAL CONVERTER MODULE-64
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
13-39
which is readable only when the test mode is enabled. Most of the bits are typically
written once when the software initializes the QADC64, and not changed afterwards.
QACR2 —
Control Register 2
0x30 480E
0x30 4C0E
MSB
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
LSB
15
CIE2
PIE2
SSE2
MQ2
RE-
SUME
BQ2
RESET:
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
Table 13-14 QACR2 Bit Descriptions
Bit(s)
Name
Description
0
CIE2
Queue 2 completion interrupt enable. CIE2 enables completion interrupts for queue 2. The inter-
rupt request is generated when the conversion is complete for the last CCW in queue 2.
0 = Queue 2 completion interrupts disabled.
1 = Generate an interrupt request after completing the last CCW in queue 2.
1
PIE2
Queue 2 pause interrupt enable. PIE2 enables pause interrupts for queue 2. The interrupt re-
quest is generated when the conversion is complete for a CCW that has the pause bit set.
0 = Queue 2 pause interrupts disabled.
1 = Generate an interrupt request after completing a CCW in queue 2 which has the pause bit set.
2
SSE2
Queue 2 single-scan enable bit. SSE2 enables a single-scan of queue 2 after a trigger event oc-
curs. The SSE2 bit may be set to a one during the same write cycle that sets the MQ2 bits for
the single-scan queue operating mode. The single-scan enable bit can be written as a one or a
zero, but is always read as a zero.
The SSE2 bit allows a trigger event to initiate queue execution for any single-scan operation on
queue 2. The QADC64 clears SSE2 when the single-scan is complete.
3:7
MQ2
Queue 2 operating mode. The MQ2 field selects the queue operating mode for queue 2.
shows the bits in the MQ2 field which enable different queue 2 operating modes.
8
RESUME
Queue 2 resume. RESUME selects the resumption point after queue 2 is suspended by queue
1. If RESUME is changed during execution of queue 2, the change is not recognized until an end-
of-queue condition is reached, or the queue operating mode of queue 2 is changed.
0 = After suspension, begin execution with the first CCW in queue 2 or the current sub-queue.
1 = After suspension, begin execution with the aborted CCW in queue 2.
9:15
BQ2
Beginning of queue 2. The BQ2 field indicates the location in the CCW table where queue 2 be-
gins. The BQ2 field also indicates the end of queue 1 and thus creates an end-of-queue condition
for queue 1. Setting BQ2 to any value
≥
64 (0b1000000) allows the entire RAM space for queue
1 CCWs.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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