PIC16F684 datasheet(51/192 Pages) MICROCHIP

51 / 192 page

DS41202F-page 49

PIC16F684

6.6

Timer1 Gate

Timer1 gate source is software configurable to be the

T1G pin or the output of Comparator 2. This allows the

device to directly time external events using T1G or

analog events using Comparator 2. See the CMCON1

source. This feature can simplify the software for a

Delta-Sigma A/D converter and many other applications.

For more information on Delta-Sigma A/D converters,

see the Microchip web site (www.microchip.com).

Timer1 gate can be inverted using the T1GINV bit of

the T1CON register, whether it originates from the T1G

pin or Comparator 2 output. This configures Timer1 to

measure either the active-high or active-low time

between events.

6.7

Timer1 Interrupt

The Timer1 register pair (TMR1H:TMR1L) increments

to FFFFh and rolls over to 0000h. When Timer1 rolls

over, the Timer1 interrupt flag bit of the PIR1 register is

set. To enable the interrupt on rollover, you must set

these bits:

• TMR1ON bit or the T1CON register

• TMR1IE bit of the PIE1 register

• PEIE bit of the INTCON register

• GIE bit of the INTCON register

The interrupt is cleared by clearing the TMR1IF bit in

the Interrupt Service Routine.

6.8

Timer1 Operation During Sleep

Timer1 can only operate during Sleep when setup in

Asynchronous Counter mode. In this mode, an external

crystal or clock source can be used to increment the

counter. To set up the timer to wake the device:

• TMR1ON bit of the T1CON register must be set

• TMR1IE bit of the PIE1 register must be set

• PEIE bit of the INTCON register must be set

• T1SYNC bit of the T1CON register

• TMR1CS bit of the T1CON register

• T1OSCEN bit of the T1CON register (can be set)

The device will wake-up on an overflow and execute

the next instruction. If the GIE bit of the INTCON

Routine (0004h).

6.9

ECCP Capture/Compare Time Base

The ECCP module uses the TMR1H:TMR1L register

pair as the time base when operating in Capture or

Compare mode.

In Capture mode, the value in the TMR1H:TMR1L

In Compare mode, an event is triggered when the value

CCPR1H:CCPR1L register pair matches the value in

the TMR1H:TMR1L register pair. This event can be a

Special Event Trigger.

For more information, see Section 11.0 “Enhanced

Capture/Compare/PWM (With Auto-Shutdown and

Dead Band) Module”.

6.10

ECCP Special Event Trigger

When the ECCP is configured to trigger a special

event, the trigger will clear the TMR1H:TMR1L register

pair. This special event does not cause a Timer1

interrupt. The ECCP module may still be configured to

generate a ECCP interrupt.

In this mode of operation, the CCPR1H:CCPR1L

Timer1.

Timer1 should be synchronized to the FOSC to utilize

the Special Event Trigger. Asynchronous operation of

Timer1 can cause a Special Event Trigger to be

missed.

In the event that a write to TMR1H or TMR1L coincides

with a Special Event Trigger from the ECCP, the write

will take precedence.

For more information, see Section 11.2.4 “Special

Event Trigger”.

6.11

Comparator Synchronization

The same clock used to increment Timer1 can also be

used to synchronize the comparator output. This

feature is enabled in the Comparator module.

When using the comparator for Timer1 gate, the

comparator output should be synchronized to Timer1.

This ensures Timer1 does not miss an increment if the

comparator changes.

For more information, see Section 8.9 “Synchronizing

Comparator C2 Output to Timer1”.

Note:

TMR1GE bit of the T1CON register must

be set to use either T1G or C2OUT as the

Timer1 gate source. See the CMCON1

tion on selecting the Timer1 gate source.

Note:

The TMR1H:TTMR1L register pair and the

TMR1IF bit should be cleared before

enabling interrupts.

PIC16F684 датащи(PDF) 51 Page - Microchip Technology

PIC16F684 датащи(HTML) 51 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL