Microchip Technology dsPIC30F - Input Capture Registers

© 2004 Microchip Technology Inc. DS70060C-page 13-3
Section 13. Input Capture
Input Capture
13
13.2 Input Capture Registers
Each capture channel available on the dsPIC30F devices has the following registers, where ‘x’
denotes the number of the capture channel:
• ICxCON: Input Capture Control Register
• ICxBUF: Input Capture Buffer Register
Register 13-1: ICxCON: Input Capture x Control Register
Upper Byte:
U-0 U-0 R/W-0 U-0 U-0 U-0 U-0 U-0
— —
ICSIDL
— — — — —
bit 15 bit 8
Lower Byte:
R/W-0 R/W-0 R/W-0 R-0, HC R-0, HC R/W-0 R/W-0 R/W-0
ICTMR ICI<1:0> ICOV ICBNE ICM<2:0>
bit 7 bit 0
bit 15-14 Unimplemented: Read as ‘0’
bit 13 ICSIDL: Input Capture Module Stop in Idle Control bit
1 = Input capture module will halt in CPU Idle mode
0 = Input capture module will continue to operate in CPU Idle mode
bit 12-8 Unimplemented: Read as ‘0’
bit 7 ICTMR: Input Capture Timer Select bits
1 = TMR2 contents are captured on capture event
0 = TMR3 contents are captured on capture event
Note: Timer selections may vary. Refer to the device data sheet for details.
bit 6-5 ICI<1:0>: Select Number of Captures per Interrupt bits
11 = Interrupt on every fourth capture event
10 = Interrupt on every third capture event
01 = Interrupt on every second capture event
00 = Interrupt on every capture event
bit 4 ICOV: Input Capture Overflow Status Flag (Read Only) bit
1 = Input capture overflow occurred
0 = No input capture overflow occurred
bit 3 ICBNE: Input Capture Buffer Empty Status (Read Only) bit
1 = Input capture buffer is not empty, at least one more capture value can be read
0 = Input capture buffer is empty
bit 2-0 ICM<2:0>: Input Capture Mode Select bits
111 = Input Capture functions as interrupt pin only, when device is in Sleep or Idle mode
(Rising edge detect only, all other control bits are not applicable.)
110 = Unused (module disabled)
101 = Capture mode, every 16th rising edge
100 = Capture mode, every 4th rising edge
011 = Capture mode, every rising edge
010 = Capture mode, every falling edge
001 = Capture mode, every edge (rising and falling)
(ICI<1:0> does not control interrupt generation for this mode.)
000 = Input capture module turned off
Legend:
HC = Cleared in Hardware HS = Set in Hardware
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown