PIC16F87XA
6.7
Resetting of Timer1 Register Pair
(TMR1H, TMR1L)
6.8
Timer1 Prescaler
The prescaler counter is cleared on writes to the
TMR1H or TMR1L registers.
TMR1H and TMR1L registers are not reset to 00h on a
POR, or any other RESET, except by the CCP1 and
CCP2 special event triggers.
T1CON register is reset to 00h on a Power-on Reset,
or a Brown-out Reset, which shuts off the timer and
leaves a 1:1 prescale. In all other RESETS, the register
is unaffected.
TABLE 6-2:
REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER
Value on: Value on
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR,
BOR
all other
RESETS
0Bh,8Bh,
INTCON
GIE
PEIE TMR0IE
INTE
RBIE
TMR0IF
INTF
RBIF 0000 000x0000 000u
10Bh, 18Bh
(1)
0Ch
8Ch
0Eh
0Fh
10h
PIR1
PIE1
PSPIF
PSPIE
ADIF
ADIE
RCIF
RCIE
TXIF
TXIE
SSPIF
SSPIE
CCP1IF TMR2IF TMR1IF
CCP1IE TMR2IE TMR1IE
0000 00000000 0000
0000 00000000 0000
xxxx xxxxuuuu uuuu
xxxx xxxxuuuu uuuu
(1)
TMR1L Holding Register for the Least Significant Byte of the 16-bit TMR1 Register
TMR1H Holding Register for the Most Significant Byte of the 16-bit TMR1 Register
T1CON
—
—
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000--uu uuuu
Legend: x= unknown, u= unchanged, -= unimplemented, read as '0'. Shaded cells are not used by the Timer1 module.
Note 1: Bits PSPIE and PSPIF are reserved on the 28-pin devices; always maintain these bits clear.
DS39582A-page 58
AdvanceInformation
2001 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
