PIC16F721-I/SO Microchip Technology, PIC16F721-I/SO Datasheet - Page 99

• Manufacturer Part Number: PIC16F721-I/SO
• Description: MCU PIC 4K FLASH 20-SOIC
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 16Fr

Specifications of PIC16F721-I/SO

• Core Size: 8-Bit
• Program Memory Size: 7KB (4K x 14)
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Core Processor: PIC
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Number Of I /o: 17
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 12x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-SOIC (0.300", 7.50mm Width)
• Controller Family/series: PIC16F
• No. Of I/o's: 18
• Ram Memory Size: 256Byte
• Cpu Speed: 16MHz
• No. Of Timers: 3
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

13.5.3
When Timer1 Gate Toggle mode is enabled, it is
possible to measure the full-cycle length of a Timer1
gate signal, as opposed to the duration of a single level
pulse.
The Timer1 gate source is routed through a flip-flop that
changes state on every incrementing edge of the sig-
nal. See
Timer1 Gate Toggle mode is enabled by setting the
T1GTM bit of the T1GCON register. When the T1GTM
bit is cleared, the flip-flop is cleared and held clear. This
is necessary in order to control which edge is
measured.
13.5.4
When Timer1 Gate Single-Pulse mode is enabled, it is
possible to capture a single pulse gate event. Timer1
Gate Single-Pulse mode is first enabled by setting the
T1GSPM bit in the T1GCON register. Next, the
T1GGO/DONE bit in the T1GCON register must be set.
The Timer1 will be fully enabled on the next
incrementing edge. On the next trailing edge of the
pulse, the T1GGO/DONE bit will automatically be
cleared. No other gate events will be allowed to
increment Timer1 until the T1GGO/DONE bit is once
again set in software.
Clearing the T1GSPM bit of the T1GCON register will
also clear the T1GGO/DONE bit. See
timing details.
Enabling the Toggle mode and the Single-Pulse mode
simultaneously will permit both sections to work
together. This allows the cycle times on the Timer1 gate
source to be measured. See
details.
 2010 Microchip Technology Inc.
Note:
Figure 13-4
TIMER1 GATE TOGGLE MODE
Enabling Toggle mode at the same time
as changing the gate polarity may result in
indeterminate operation.
TIMER1 GATE SINGLE-PULSE
MODE
for timing details.
Figure 13-6
Figure 13-5
for timing
for
13.5.5
When Timer1 gate value status is utilized, it is possible
to read the most current level of the gate control value.
The value is stored in the T1GVAL bit in the T1GCON
register. The T1GVAL bit is valid even when the Timer1
gate is not enabled (TMR1GE bit is cleared).
13.5.6
When Timer1 gate event interrupt is enabled, it is
possible to generate an interrupt upon the completion
of a gate event. When the falling edge of T1GVAL
occurs, the TMR1GIF flag bit in the PIR1 register will be
set. If the TMR1GIE bit in the PIE1 register is set, then
an interrupt will be recognized.
The TMR1GIF flag bit operates even when the Timer1
gate is not enabled (TMR1GE bit is cleared).
PIC16F/LF720/721
TIMER1 GATE VALUE STATUS
TIMER1 GATE EVENT INTERRUPT
DS41430A-page 99