MMC2114 MOTOROLA [Motorola, Inc], MMC2114 Datasheet - Page 499

• Manufacturer Part Number: MMC2114
• Description: M CORE Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

19.10.7 Continuous-Scan Modes
MMC2114 • MMC2113 • MMC2112 — Rev. 1.0
MOTOROLA
NOTE:
NOTE:
A continuous-scan queue operating mode is used to execute multiple
passes through a sequence of conversions defined by a queue. By
programming the MQ1 field in QACR1 or the MQ2 field in QACR2, these
modes can be selected:
Queue 2 cannot be programmed for externally gated continuous-scan
mode.
When a queue is programmed for a continuous-scan mode, the
single-scan enable bit in the queue control register does not have any
meaning or effect. As soon as the queue operating mode is
programmed, the selected trigger event can initiate queue execution.
In the case of software-initiated continuous-scan mode, the trigger event
is generated internally and queue execution begins immediately. In the
other continuous-scan queue operating modes, the selected trigger
event must occur before the queue can start. A trigger overrun is
captured if a trigger event occurs during queue execution in the
externally triggered continuous-scan mode or the periodic timer
continuous-scan mode.
After queue execution is complete, the queue status is shown as idle.
Because the continuous-scan queue operating modes allow the entire
queue to be scanned multiple times, software involvement is not needed
for queue execution to continue from the idle state. The next trigger
event causes queue execution to begin again, starting with the first CCW
in the queue.
In continuous-scan modes, all samples are guaranteed to be taken
during one pass through the queue (coherently), except when a queue 1
trigger event halts queue 2 execution. The time between consecutive
conversions has been designed to be consistent. However, for queues
that end with a CCW containing the EOQ code (channel 63), the time
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Freescale Semiconductor, Inc.
For More Information On This Product,
Queued Analog-to-Digital Converter (QADC)
Software-initiated continuous-scan mode
Externally triggered continuous-scan mode
Externally gated continuous-scan mode
Periodic timer continuous-scan mode
Go to: www.freescale.com
Queued Analog-to-Digital Converter (QADC)
Advance Information
Digital Control
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