Microcontroller User's Manual

27-18 MCF5282 User’s Manual MOTOROLA
Register Descriptions
Table 27-8. QACR2 Field Descriptions
Bit(s) Name Description
15 CIE2 Queue 2 completion software interrupt enable. Enables an interrupt request upon completion of
queue 2. The interrupt request is initiated when the conversion is complete for the last CCW in
queue 2.
1 Enable queue 2 completion interrupt.
0 Disable queue 2 completion interrupt.
14 PIE2 Queue 2 pause interrupt enable. Enables an interrupt request when queue 2 enters the pause
state. The interrupt request is initiated when conversion is complete for a CCW that has the
pause bit set.
1 Enable the queue 2 pause interrupt.
0 Disable the queue 2 pause interrupt.
13 SSE2 Queue 2 single-scan enable. Enables a single-scan of queue 2 after a trigger event occurs. SSE2
may be set during the same write cycle that sets the MQ2 bits for one of the single-scan queue
operating modes. The single-scan enable bit can be written to 1 or 0, but is always read as a 0,
unless the QADC is in test mode. The QADC clears SSE2 when the single-scan is complete.
1 Allow a trigger event to start queue 2 in a single-scan mode.
0 Trigger events are ignored for queue 2 single-scan modes.
12–8 MQ2 Selects the operating mode for queue 2. Table 27-9 shows the bits in the MQ1 field which
enable different queue 2 operating modes.
7 RESUME Selects the resumption point for queue 2 after its operation is suspended due to a queue 1 trigger
event. If RESUME is changed during the execution of queue 2, the change is not recognized
until an end-of-queue condition is reached or the operating mode of queue 2 is changed.
1 After suspension, begin execution with the aborted CCW in queue 2.
0 After suspension, begin execution with the first CCW of queue 2 or the current subqueue of
queue 2.
6–0 BQ2 Beginning of queue 2. Denotes the CCW location where queue 2 begins. This allows the length
of queue 1 and queue 2 to vary. The BQ2 field also serves as an end-of-queue condition for
queue 1.
Table 27-9. Queue 2 Operating Modes
MQ2[12:8] Operating Modes
00000 Disabled mode, conversions do not occur
00001 Software triggered single-scan mode (started with SSE2)
00010 Externally triggered rising edge single-scan mode
00011 Externally triggered falling edge single-scan mode
00100 Interval timer single-scan mode: time = QCLK period x 2
7
00101 Interval timer single-scan mode: time = QCLK period x 2
8
00110 Interval timer single-scan mode: time = QCLK period x 2
9
00111 Interval timer single-scan mode: time = QCLK period x 2
10
01000 Interval timer single-scan mode: time = QCLK period x 2
11
01001 Interval timer single-scan mode: time = QCLK period x 2
12
01010 Interval timer single-scan mode: time = QCLK period x 2
13