PIC18F87K22 Datasheet, PDF (271/548 Pages) Microchip Technology – 64/80-Pin, High-Performance, 1-Mbit Enhanced Flash Microcontrollers with 12-Bit A/D and nanoWatt XLP Technology

PIC18F87K22 FAMILY
When a shutdown event occurs, two things happen:
• The ECCPxASE bit is set to ‘1’. The ECCPxASE
will remain set until cleared in firmware or an
auto-restart occurs. (See Section 20.4.5
“Auto-Restart Mode”.)
• The enabled PWM pins are asynchronously
placed in their shutdown states. The PWM output
pins are grouped into pairs (PxA/PxC) and
(PxB/PxD). The state of each pin pair is
determined by the PSSxAC and PSSxBD bits
(ECCPxAS<3:2> and <1:0>, respectively).
Each pin pair may be placed into one of three states:
• Drive logic ‘1’
• Drive logic ‘0’
• Tri-state (high-impedance)
REGISTER 20-3: ECCPxAS: ECCPx AUTO-SHUTDOWN CONTROL REGISTER
R/W-0
ECCPxASE
bit 7
R/W-0
R/W-0
R/W-0
ECCPxAS2 ECCPxAS1 ECCPxAS0
R/W-0
PSSxAC1
R/W-0
PSSxAC0
R/W-0
PSSxBD1
R/W-0
PSSxBD0
bit 0
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
bit 6-4
bit 3-2
bit 1-0
ECCPxASE: ECCP Auto-Shutdown Event Status bit
1 = A shutdown event has occurred; ECCP outputs are in a shutdown state
0 = ECCP outputs are operating
ECCPxAS<2:0>: ECCP Auto-Shutdown Source Select bits
000 = Auto-shutdown is disabled
001 = Comparator C1OUT output is high
010 = Comparator C2OUT output is high
011 = Either Comparator C1OUT or C2OUT is high
100 = VIL on FLT0 pin
101 = VIL on FLT0 pin or Comparator C1OUT output is high
110 = VIL on FLT0 pin or Comparator C2OUT output is high
111 = VIL on FLT0 pin or Comparator C1OUT or Comparator C2OUT is high
PSSxAC<1:0>: Pins PxA and PxC Shutdown State Control bits
00 = Drive pins, PxA and PxC, to ‘0’
01 = Drive pins, PxA and PxC, to ‘1’
1x = Pins, PxA and PxC, tri-state
PSSxBD<1:0>: Pins PxB and PxD Shutdown State Control bits
00 = Drive pins, PxB and PxD, to ‘0’
01 = Drive pins, PxB and PxD, to ‘1’
1x = Pins, PxB and PxD, tri-state
Note 1: The auto-shutdown condition is a level-based signal, not an edge-based signal. As long as the level is
present, the auto-shutdown will persist.
2: Writing to the ECCPxASE bit is disabled while an auto-shutdown condition persists.
3: Once the auto-shutdown condition has been removed and the PWM restarted (either through firmware or
auto-restart), the PWM signal will always restart at the beginning of the next PWM period.
 2010 Microchip Technology Inc.
Preliminary
DS39960B-page 271