NXP Semiconductors MPC5566, Reference Manual

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Enhanced Modular Input/Output Subsystem (eMIOS)
MPC5566 Microcontroller Reference Manual, Rev. 2
Freescale Semiconductor 17-35
Figure 17-22 describes the A1 and B1 register updates when EMIOS_CADR n and EMIOS_CBDR n read
operations are performed. When an EMIOS_CADR n read occurs the content of A1 is transferred to B1
thus providing coherent data in the A2 and B1 registers. Transfers from B2 to B1 are then blocked until
EMIOS_CBDR
n is read. After EMIOS_CBDR n is read, register A1 content is transferred to register B1
and the transfers from B2 to B1 are re-enabled to occur at the transfer edges, which is the leading edge in
the
Figure 17-22 example.
Figure 17-22. A1 and B1 Updates at EMIOS_CADR and EMIOS_CBDR Reads
17.4.4.4.6 Double-action Output Compare Mode (DAOC)
The following table lists the double-action output compare mode settings:
In the DAOC mode the leading and trailing edges of the variable pulse-width output are generated by
matches occurring on comparators A and B, respectively.
When the DAOC mode is first selected (coming from GPIO mode) both comparators are disabled.
Comparators A and B are enabled by updating registers A1 and B1 respectively and remain enabled until
a match occurs on that comparator, when it is disabled again. To update registers A1 and B1, a write to A2
and B2 must occur and the EMIOS_CCR
n [ODIS] bit must be cleared.
The output flip-flop is set to the value of EMIOS_CCR n [EDPOL] when a match occurs on comparator A
and to the complement of EDPOL when a match occurs on comparator B.
Table 17-19. DAOC Operating Modes
MODE[0:6] Unified Channel DAOC Operating Mode
0b0000110 Double-action output compare (with FLAG set on the second match)
0b0000111 Double-action output compare (with FLAG set on both matches)
0x000500 0x001000 0x001100 0x001250 0x001525 0x0016A0
Selected
counter bus
FLAG
set event
A A A
Captured A2
value
2
0xxxxxxx
Notes:
1
After input filter.
2
Reading EMIOS_CADR n returns the value of A2.
Input signal
1
EDPOL = 1
B1 value
3
0x001525
0xxxxxxx
0xxxxxxx
0x001000 0x001250
Captured B2
value
3
Reading EMIOS_CBDR n returns the value of B1.
0xxxxxxx 0x001000 0x001250
A1 value
Read MTSA[n] Read MTSB[ n ]
0x001250
0x001000
0x001000
0x0016A0
0x001100
0x001250