Motorola MPC533 Reference Manual page 756

MIOS14 Double Action Submodule (MDASM)
Mode selection; EDPOL = 0 (Channel A capture on rising edge)
Input signal
FLAG bit
16-bit
0x0500
Counter Bus
Register A
0xxxxx
Internal Register, not accessible to
Register B1
0xxxxx
Register B2
0xxxxx
Figure 17-16. Input Period Measurement Example
17.9.5 Input Capture (IC) Mode
IC mode is selected by setting MODE[0:3] to 0b0011. This mode is identical to the input
period measurement mode (IPM) described above, with the exception that the FLAG line
is also activated at the occurrence of the first detected edge of the selected polarity. In this
mode the MDASM functions as a standard input capture function. In this case the value
latched in channel B can be ignored. Figure 17-17 provides an example of how the
MDASM can be used for input capture.
Mode selection; EDPOL = 0 (Channel A capture on rising edge)
Input signal
FLAG bit
16-bit
0x0500
Counter Bus
Register A
0xxxxx
Internal Register, not accessible to software
Register B1
0xxxxx
Register B2
0xxxxx
(Ignored)
17-32
PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
Rising
Edge Trigger
0x1000 0x1100
1
0x1000
3 software
0x1000
2
0xxxxx
Rising
Edge Trigger
FLAG reset
by software
Flag set
0x1000 0x1100
0x1000 0x1000
0x1000 0x1000
0xxxxx 0xxxxx
Figure 17-17. MDASM Input Capture Example
MPC533 Reference Manual
Rising
Edge Trigger
Flag set
0x1400
1
0x1000 0x1400
3
0x1000 0x1400
2 Flag set
0xxxxx 0x0400
Period = Reg A -Reg B
Rising
Edge Trigger
FLAG reset
by software
Flag set
0x1400
0x1400
0x1400
0x1000
Rising
Edge Trigger
FLAG reset
FLAG reset
by software
by softwa re
Flag set
0x1525 0x16A0
0x1400 0x16A0
0x1400 0x16A0
2 Flag set
0x1000 0x1400
Period = Reg A -Reg B
Rising
Edge Trigger
FLAG reset
by software
Flag set
0x1525 0x16A0
0x1400 0x16A0
0x1400 0x16A0
0x1000 0x1400
MOTOROLA
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