CMX838 View Datasheet(PDF) - CML Microsystems Plc
Part Name
Description
MFG CO.
'CMX838' PDF : 71 Pages View PDF
FRS/PMR446/GMRS Family Radio Processor
CMX838
wait ≥ 250µs
$93 0x60 (enable interrupts)
4.2.4.5 Initialize and Configure
4.2.4.5.1 Enter Fast Initialization Mode (Task 12)
Issuing task 12 takes the tone signaling processor out of normal running mode and dedicates the processor to
handling initialization tasks to increase the maximum task rate. In this mode neither the tone encoders nor the
decoders run. To return to normal running mode issue task 0. In this fast initialization mode tasks can be
issued at a rate of one per 50µs. Ensure that the required argument registers are not updated for at least this
time after a task is issued.
4.2.4.5.2 Quickly Enable/Disable Multiple Detectors (Task 13)
Issuing task 13 places the tone signaling processor in a mode that allows multiple detectors to be to be
quickly configured. Like for task 12 neither the tone encoders nor the decoders run in this mode. The
argument data is defined as for task 4. This mode reverts to Fast Initialization Mode when any other task is
issued. To return to normal running mode issue task 0. The following example shows how to enable only
Tone detectors 1, 7, 10, 12, 18, and 20. Multiple calls to Task 4 can accomplish this, but would require more
C-BUS transactions and waiting 250µs after each task 4 call, but could allow the tone decoders to continue to
run.
// to disable all tone detectors and enter mode to quickly enable multiple detectors
$95 0x3F
$93 0x4D
// value = 0x40 | 0x0D
wait 250µs
$95 0x81
// to ensure device runs Task 13
// to enable tone detector 1 (67.0 Hz) value = 0x80 | 0x01
wait 50µs
$95 0x87
// to ensure task completes
// to enable tone detector 7 (82.5 Hz)
wait 50µs
$95 0x8A
// to ensure task completes
// to enable tone detector 10 (91.5 Hz)
wait 50µs
$95 0x8C
// to ensure task completes
// to enable tone detector 12 (97.4 Hz)
wait 50µs
$95 0x92
// to ensure task completes
// to enable tone detector 18 (118.8 Hz)
wait 50µs
$95 0x94
// to ensure task completes
// to enable tone detector 20 (127.3 Hz)
wait 50µs
// to ensure task completes
// to place device back in normal running mode
$93 Power Control + IRQ Control + Task 0
2003 CML Microsystems Plc
24
D/838/8
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