dspic33fj128gp204 Microchip Technology Inc., dspic33fj128gp204 Datasheet - Page 185

• Manufacturer Part Number: dspic33fj128gp204
• Description: High-performance, 16-bit Digital Signal Controllers
• Manufacturer: Microchip Technology Inc.

12.0
The Timer1 module is a 16-bit timer, which can serve
as the time counter for the real-time clock, or operate
as a free-running interval timer/counter.
The Timer1 module has the following unique features
over other timers:
• Can be operated from the low power 32 kHz
• Can be operated in Asynchronous Counter mode
• The external clock input (T1CK) can optionally be
The unique features of Timer1 allow it to be used for
Real-Time Clock (RTC) applications. A block diagram
of Timer1 is shown in Figure 12-1.
FIGURE 12-1:
© 2009 Microchip Technology Inc.
Note:
crystal oscillator available on the device
from an external clock source.
synchronized to the internal device clock and the
clock synchronization is performed after the
prescaler.
SOSCO/
SOSCI
T1CK
Note 1: Refer to Section 9.0 “Oscillator Configuration” for information on enabling the secondary oscillator.
TIMER1
This data sheet summarizes the features
of
dsPIC33FJ64GPX02/X04
dsPIC33FJ128GPX02/X04
devices. It is not intended to be a compre-
hensive reference source. To complement
the information in this data sheet, refer to
the “dsPIC33F Family Reference Manual”,
“Section 11. Timers” (DS70205), which
is available from the Microchip website
(www.microchip.com).
the
LPOSCEN
16-BIT TIMER1 MODULE BLOCK DIAGRAM
dsPIC33FJ32GP302/304,
(1)
F
TCKPS<1:0>
Prescaler
CY
(/n)
TCKPS<1:0>
Prescaler
Sync
Gate
families
(/n)
and
Sync
Preliminary
of
TSYNC
Falling Edge
Detect
1
0
TGATE
The Timer1 module can operate in one of the following
modes:
• Timer mode
• Gated Timer mode
• Synchronous Counter mode
• Asynchronous Counter mode
In Timer and Gated Timer modes, the input clock is
derived from the internal instruction cycle clock (F
In Synchronous and Asynchronous Counter modes,
the input clock is derived from the external clock input
at the T1CK pin.
The Timer modes are determined by the following bits:
• Timer Clock Source Control bit (TCS): T1CON<1>
• Timer Synchronization Control bit (TSYNC):
• Timer Gate Control bit (TGATE): T1CON<6>
Timer control bit setting for different operating modes
are given in the Table 12-1.
TABLE 12-1:
Timer
Gated timer
Synchronous
counter
Asynchronous
counter
TCS
T1CON<2>
Mode
10
00
x1
Comparator
TIMER MODE SETTINGS
TMR1
PR1
TCS
0
0
1
1
Reset
Equal
TGATE
TGATE
0
1
x
x
DS70292C-page 183
1
0
Set T1IF flag
TSYNC
x
x
1
0
CY
).