Datasheet

© 2010 Microchip Technology Inc. DS70135G-page 81
dsPIC30F4011/4012
12.0 INPUT CAPTURE MODULE
This section describes the input capture module and
associated operational modes. The features provided by
this module are useful in applications requiring
frequency (period) and pulse measurement. Figure 12-1
depicts a block diagram of the input capture module.
Input capture is useful for such modes as:
• Frequency/Period/Pulse Measurements
• Additional Sources of External Interrupts
The key operational features of the input capture
module are:
• Simple Capture Event mode
• Timer2 and Timer3 mode selection
• Interrupt on input capture event
These operating modes are determined by setting the
appropriate bits in the ICxCON register (where x = 1, 2,
...N). The dsPIC30F4011/4012 devices have four
capture channels.
FIGURE 12-1: INPUT CAPTURE MODE BLOCK DIAGRAM
Note: This data sheet summarizes features of
this group of dsPIC30F devices and is not
intended to be a complete reference
source. For more information on the CPU,
peripherals, register descriptions and
general device functionality, refer to the
dsPIC30F Family Reference Manual
(DS70046). For more information on the
device instruction set and programming,
refer to the “16-bit MCU and DSC
Reference Manual” (DS70157).
Note: The dsPIC30F4011/4012 devices have
four capture inputs: IC1, IC2, IC7 and IC8.
The naming of these four capture chan-
nels is intentional and preserves software
compatibility with other dsPIC Digital
Signal Controllers.
ICxBUF
Prescaler
ICx
ICM<2:0>
Mode Select
3
Note: Where ‘x’ is shown, reference is made to the registers or bits associated to the respective input capture
channels 1 through N.
10
Set Flag
Pin
ICxIF
ICTMR
T2_CNT
T3_CNT
Edge
Detection
Logic
Clock
Synchronizer
1, 4, 16
From Timer Module
16 16
FIFO
R/W
Logic
ICI<1:0>
ICBNE, ICOV
ICxCON
Interrupt
Logic
Set Flag
ICxIF
Data Bus