PIC16F87 Datasheet, PDF (107/214 Pages) Microchip Technology – 18/20/28-Pin Enhanced FLASH Microcontrollers with nanoWatt Technology

PIC16F87/88
When setting up an asynchronous reception, follow
these steps:
1. Initialize the SPBRG register for the appropriate
baud rate. If a high-speed baud rate is desired,
set bit BRGH (Section 11.1 “USART Baud
Rate Generator (BRG)”).
2. Enable the asynchronous serial port by clearing
bit SYNC and setting bit SPEN.
3. If interrupts are desired, then set enable bit
RCIE.
4. If 9-bit reception is desired, then set bit RX9.
5. Enable the reception by setting bit CREN.
6. Flag bit RCIF will be set when reception is com-
plete and an interrupt will be generated if enable
bit RCIE is set.
7. Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
8. Read the 8-bit received data by reading the
RCREG register.
9. If any error occurred, clear the error by clearing
enable bit CREN.
10. If using interrupts, ensure that GIE and PEIE
(bits 7 and 6) of the INTCON register are set.
TABLE 11-8: REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Address Name Bit 7
Bit 6
Bit 5 Bit 4 Bit 3 Bit 2
Bit 1
Bit 0
Value on:
POR, BOR
Value on
all other
RESETS
0Bh, 8Bh, INTCON GIE
10Bh,18Bh
PEIE TMR0IE INTE RBIE TMR0IF INTF R0IF 0000 000x 0000 000u
0Ch
PIR1
—
ADIF RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF -000 0000 -000 0000
18h
RCSTA SPEN RX9 SREN CREN — FERR OERR RX9D 0000 -00x 0000 -00x
1Ah
RCREG USART Receive Register
0000 0000 0000 0000
8Ch
PIE1
—
ADIE RCIE TXIE SSPIE CCP1IE TMR2IE TMR1IE -000 0000 -000 0000
98h
TXSTA CSRC TX9 TXEN SYNC — BRGH TRMT TX9D 0000 -010 0000 -010
99h
SPBRG Baud Rate Generator Register
0000 0000 0000 0000
Legend: x = unknown, - = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous reception.
 2003 Microchip Technology Inc.
Preliminary
DS30487B-page 105