MPC5553/MPC5554 Microcontroller Reference Manual, Rev. 5
17-40
Freescale Semiconductor
The MC mode can be used to provide a time base for a counter bus or as a general purpose timer.
MODE[6] bit selects internal or external clock source when cleared or set, respectively. When external
clock is selected, the input signal pin is used as the source and the triggering polarity edge is selected by
the EDPOL and EDSEL in the EMIOS_CCR
n
.
When software selects the modulus counter mode, the internal counter is initially reset to 0. The internal
counter counts up from the current value until it matches the value in register A1. Register B1 is cleared
and is not accessible to the MCU. MODE[4] bit selects up mode or up/down mode, when cleared or set,
respectively.
When in up count mode, a match between the internal counter and register A1 sets the FLAG and clears
the internal counter.
When in up/down count mode, a match between the internal counter and register A1 sets the FLAG and
changes the counter direction from increment to decrement. A match between register B1 and the internal
counter changes the counter direction from decrement to increment and sets the FLAG only if MODE[5]
bit is set.
NOTE
The FORCMA and FORCMB bits have no effect when the unified channel
is configured for MC mode.
NOTE
Any update to the A register will take place immediately, regardless of the
current state of the counter and whether the counter is in up mode, or
up/down mode.
and
shows how the unified channel can be used as modulus counter in up mode
and up/down mode, respectively.
0b0010101
Modulus counter
(up/down counter, no change in counter direction upon match of input
counter and register B1, external clock source)
0b0010110
Modulus counter
(up/down counter, change in counter direction upon match of input counter
and register B1 and sets the FLAG, internal clock source)
0b0010111
Modulus counter
(up/down counter, change in counter direction upon match of input counter
and register B1 and sets the FLAG, external clock source)
Table 17-23. Mode of Operation: MC Mode (Continued)
MODE[0:6]
Unified Channel Mode of Operation
Summary of Contents for MPC5553
Page 5: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 2 Freescale Semiconductor...
Page 21: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 xvi Freescale Semiconductor...
Page 47: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 1 26 Freescale Semiconductor...
Page 163: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 4 20 Freescale Semiconductor...
Page 179: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 5 16 Freescale Semiconductor...
Page 561: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 13 38 Freescale Semiconductor...
Page 615: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 14 54 Freescale Semiconductor...
Page 707: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 17 68 Freescale Semiconductor...
Page 755: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 18 48 Freescale Semiconductor...
Page 873: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 19 118 Freescale Semiconductor...
Page 984: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 Freescale Semiconductor 21 41...
Page 985: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 21 42 Freescale Semiconductor...
Page 1019: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 22 34 Freescale Semiconductor...
Page 1129: ...MPC5553 MPC5554 Microcontroller Reference Manual Rev 5 25 90 Freescale Semiconductor...