PIC16F688-I/P Microchip Technology, PIC16F688-I/P Datasheet - Page 79

• Manufacturer Part Number: PIC16F688-I/P
• Description: IC PIC MCU FLASH 4KX14 14DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F688-I/P

• Program Memory Type: FLASH
• Program Memory Size: 7KB (4K x 14)
• Package / Case: 14-DIP (0.300", 7.62mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: UART/USART
• Peripherals: Brown-out Detect/Reset, POR, WDT
• Number Of I /o: 12
• Eeprom Size: 256 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: SCI/USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 2
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DM163014, DM164120-4
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• Data Rom Size: 256 B
• Height: 3.3 mm
• Length: 19.05 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2 V
• Width: 6.35 mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC162066 - HEADER INTRFC MPLAB ICD2 20PINAC162061 - HEADER INTRFC MPLAB ICD2 20PINDM163029 - BOARD PICDEM FOR MECHATRONICSAC162056 - HEADER INTERFACE ICD2 16F688ACICE0207 - MPLABICE 14P 300 MIL ADAPTERAC124001 - MODULE SKT PROMATEII 8DIP/SOIC
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

10.0
The Enhanced Universal Synchronous Asynchronous
Receiver Transmitter (EUSART) module is the serial
I/O module available for PIC16F688 . (EUSART is also
known as a Serial Communications Interface or SCI).
The EUSART can be configured as a full-duplex
asynchronous system that can communicate with
peripheral devices, such as CRT terminals and
personal computers. It can also be configured as a
half-duplex synchronous system that can communicate
with peripheral devices, such as A/D or D/A integrated
circuits, serial EEPROMs, etc.
The EUSART module implements additional features,
including
calibration, automatic wake-up on Break reception and
13-bit Break character transmit. These make it ideally
suited for use in Local Interconnect Network (LIN) bus
systems.
The USART can be configured in the following modes:
• Asynchronous (full-duplex) with:
• Synchronous – Master (half-duplex) with
• Synchronous – Slave (half-duplex) with selectable
In order to configure pins RC4/C2OUT/TX/CK and
RC5/RX/DT
Asynchronous Receiver Transmitter:
• SPEN (RCSTA<7>) bit must be set (= 1),
• TRISC<5> bit must be set (= 1), and
• TRISC<4> bit must be set (= 1).
The operation of the EUSART module is controlled
through three registers:
• Transmit Status and Control (TXSTA)
• Receive Status and Control (RCSTA)
• Baud Rate Control (BAUDCTL)
These are detailed in on the following pages in
Register 10-1,
respectively.
 2004 Microchip Technology Inc.
- Auto-wake-up on Break
- Auto baud calibration
- 13-bit Break character transmission
selectable clock polarity
clock polarity
Note:
ENHANCED UNIVERSAL
ASYNCHRONOUS RECEIVER
TRANSMITTER (EUSART)
automatic
The USART control will automatically
reconfigure the pin from input to output as
needed.
as
Register 10-2
the
baud
Universal
rate
and
detection
Register 10-3,
Synchronous
and
Preliminary
10.1
The factory calibrates the internal oscillator block out-
put (INTOSC) for 8 MHz. However, this frequency may
drift as V
affects the asynchronous baud rate. Two methods may
be used to adjust the baud rate clock, but both require
a reference clock source of some kind.
The first (preferred) method uses the OSCTUNE
register to adjust the INTOSC output back to 8 MHz.
Adjusting the value in the OSCTUNE register allows for
fine resolution changes to the system clock source (see
Section 3.4 “Internal Clock Modes” for more
information).
The other method adjusts the value in the baud rate
generator. There may not be fine enough resolution
when adjusting the Baud Rate Generator to compensate
for a gradual change in the peripheral clock frequency.
Clock Accuracy With
Asynchronous Operation
DD
or temperature changes, and this directly
PIC16F688
DS41203B-page 77