MPC555 / MPC556
TPU ROM FUNCTIONS
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
D-6
D.3 Queued Output Match TPU Function (QOM)
QOM can generate single or multiple output match events from a table of offsets in pa-
rameter RAM. Loop modes allow complex pulse trains to be generated once, a spec-
ified number of times, or continuously. The function can be triggered by a link from
another TPU channel. In addition, the reference time for the sequence of matches can
be obtained from another channel. QOM can generate pulse-width modulated wave-
forms, including waveforms with high times of 0% or 100%. QOM also allows a TPU
channel to be used as a discrete output pin. See Motorola TPU Progamming Note
Queued Output Match TPU Function (QOM),
(TPUPN01/D)
.
shows all of the host interface areas for the QOM function. The bit encod-
ings shown in
describe the corresponding fields in parameter RAM.
Table D-3 QOM Bit Encoding
A
Timebase Selection
0
Use TCR1 as Timebase
1
Use TCR2 as Timebase
Edge Selection
0
Falling Edge at Match
1
Rising Edge at Match
B:C
Reference for First Match
00
Immediate TCR Value
01
Last Event Time
10
Value Pointed to by REF_ADDR
11
Last Event Time
F
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Freescale Semiconductor, Inc.
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