PIC16F877A-I/PT Microchip Technology Inc., PIC16F877A-I/PT Datasheet - Page 102

• Manufacturer Part Number: PIC16F877A-I/PT
• Description: 44 PIN, 7 KB FLASH, 368 RAM, 33 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F877A-I/PT

• A/d Inputs: 8-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 5 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 33
• Interface: I2C/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 44-pin TQFP
• Programmable Memory: 14K Bytes
• Ram Size: 368 Bytes
• Speed: 20 MHz
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

PIC16F87X
When setting up an Asynchronous Transmission,
follow these steps:
1.
2.
3.
4.
FIGURE 10-2:
FIGURE 10-3:
TABLE 10-5:
DS30292C-page 100
0Bh, 8Bh,
10Bh,18Bh
0Ch
18h
19h
8Ch
98h
99h
Legend: x = unknown, - = unimplemented locations read as '0'. Shaded cells are not used for asynchronous transmission.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16F873/876; always maintain these bits clear.
Address
Write to TXREG
BRG Output
(Shift Clock)
RC6/TX/CK (pin)
TXIF bit
(Interrupt Reg. Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
Write to TXREG
BRG Output
(Shift Clock)
RC6/TX/CK (pin)
TXIF bit
(Transmit Buffer
Reg. Empty Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
Initialize the SPBRG register for the appropriate
baud rate. If a high speed baud rate is desired,
set bit BRGH (Section 10.1).
Enable the asynchronous serial port by clearing
bit SYNC and setting bit SPEN.
If interrupts are desired, then set enable bit
TXIE.
If 9-bit transmission is desired, then set transmit
bit TX9.
Note:
INTCON
PIR1
RCSTA
TXREG USART Transmit Register
PIE1
TXSTA
SPBRG Baud Rate Generator Register
Name
This timing diagram shows two consecutive transmissions.
REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
PSPIE
PSPIF
ASYNCHRONOUS MASTER TRANSMISSION
ASYNCHRONOUS MASTER TRANSMISSION (BACK TO BACK)
CSRC
SPEN
Bit 7
GIE
Word 1
Transmit Shift Reg.
Word 1
Transmit Shift Reg
Word 1
Word 1
(1)
(1)
PEIE
ADIF
ADIE
Bit 6
RX9
TX9
START Bit
START Bit
Word 2
SREN
TXEN
RCIF
RCIE
Bit 5
T0IE
Bit 0
CREN
SYNC
Bit 0
INTE
TXIE
Bit 4
TXIF
SSPIF CCP1IF
SSPIE CCP1IE TMR2IE
RBIE
Bit 3
Bit 1
—
—
Word 1
Bit 1
Word 1
5.
6.
7.
8.
BRGH
FERR
Bit 2
T0IF
Enable the transmission by setting bit TXEN,
which will also set bit TXIF.
If 9-bit transmission is selected, the ninth bit
should be loaded in bit TX9D.
Load data to the TXREG register (starts trans-
mission).
If using interrupts, ensure that GIE and PEIE
(bits 7 and 6) of the INTCON register are set.
TMR2IF
OERR
TRMT
Bit 1
INTF
Bit 7/8
Word 2
Transmit Shift Reg.
Bit 7/8
TMR1IF
TMR1IE
RX9D
TX9D
Bit 0
R0IF
STOP Bit START Bit
2001 Microchip Technology Inc.
STOP Bit
0000 000x
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
Value on:
POR,
BOR
Word 2
0000 000u
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
Value on
all other
RESETS
Bit 0