MPC555CME Freescale Semiconductor, MPC555CME Datasheet - Page 427

• Manufacturer Part Number: MPC555CME
• Description: KIT EVALUATION FOR MPC555
• Manufacturer: Freescale Semiconductor
• Type: Microcontrollerr

Specifications of MPC555CME

• Contents: Module Board, Installation Guide, Power Supply, Cable, Software and more
• Processor To Be Evaluated: MPC555
• Data Bus Width: 32 bit
• Interface Type: RS-232
• For Use With/related Products: MPC555
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

13.10.1 Queue Priority
MPC555
USER’S MANUAL
occur for Queue 1 and Queue 2
Queue 1 active/trigger event
Queue 2 active/trigger event
Simultaneous trigger events
be created within the two queues. Each queue can be operated using several different
scan modes. The scan modes for queue 1 and queue 2 are programmed in QACR1
and QACR2. Once a queue has been started by a trigger event (any of the ways to
cause the QADC64 to begin executing the CCWs in a queue or sub-queue), the
QADC64 performs a sequence of conversions and places the results in the result word
table.
Queue 1 has execution priority over queue 2 execution.
tions under which queue 1 asserts its priority:
Figure 13-7
queues. Queue 1 is shown with four CCWs in each sub-queue and queue 2 has two
CCWs in each sub-queue.
sub-queues paused
occurs for Queue 2
occurs for Queue 1
Queue State
/
MPC556 QUEUED ANALOG-TO-DIGITAL CONVERTER MODULE-64
Inactive
shows the CCW format and an example of using pause to create sub-
Table 13-3 Queue 1 Priority Assertion
A trigger event for queue 1 or queue 2 causes the corresponding queue execution to
begin.
Queue 2 cannot begin execution until queue 1 reaches completion or the paused
state. The status register records the trigger event by reporting the queue 2 status as
trigger pending. Additional trigger events for queue 2, which occur before execution
can begin, are recorded as trigger overruns.
The current queue 2 conversion is aborted. The status register reports the queue 2
status as suspended. Any trigger events occurring for queue 2 while queue 2 is sus-
pended are recorded as trigger overruns. Once queue 1 reaches the completion or
the paused state, queue 2 begins executing again. The programming of the resume
bit in QACR2 determines which CCW is executed in queue 2.
Queue 1 begins execution and the queue 2 status is changed to trigger pending.
The pause feature can be used to divide queue 1 and/or queue 2 into multiple sub-
queues. A sub-queue is defined by setting the pause bit in the last CCW of the sub-
queue.
Rev. 15 October 2000
Result
Table 13-3
shows the condi-
MOTOROLA
13-15