Motorola ColdFire MCF5281 User Manual
Page 554
Queued Analog-to-Digital Converter (QADC)
28-16
Freescale Semiconductor
Table 28-8. 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.
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 28-9. 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
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3