Datasheet
PIC16F87XA
DS39582C-page 120 2001-2013 Microchip Technology Inc.
FIGURE 10-7: ASYNCHRONOUS RECEPTION WITH ADDRESS DETECT
FIGURE 10-8: ASYNCHRONOUS RECEPTION WITH ADDRESS BYTE FIRST
TABLE 10-7: REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Start
bit
bit 1bit 0
bit 8 bit 0Stop
bit
Start
bit bit 8
Stop
bit
RC7/RX/DT
Load RSR
Read
RCIF
Word 1
RCREG
Bit 8 = 0, Data Byte Bit 8 = 1, Address Byte
Note: This timing diagram shows a data byte followed by an address byte. The data byte is not read into the RCREG (Receive Buffer)
because ADDEN = 1.
(pin)
Start
bit
bit 1bit 0
bit 8 bit 0Stop
bit
Start
bit bit 8
Stop
bit
RC7/RX/DT
Load RSR
Read
RCIF
Word 1
RCREG
Bit 8 = 1, Address Byte Bit 8 = 0, Data Byte
Note: This timing diagram shows a data byte followed by an address byte. The data byte is not read into the RCREG (Receive Buffer)
because ADDEN was not updated and still = 0.
(pin)
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,
10Bh,18Bh
INTCON GIE PEIE
TMR0IE INTE RBIE TMR0IF INTF R0IF 0000 000x 0000 000u
0Ch PIR1
PSPIF
(1)
ADIF RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000
18h RCSTA SPEN RX9
SREN CREN ADDEN FERR OERR RX9D 0000 000x 0000 000x
1Ah RCREG USART Receive Register 0000 0000 0000 0000
8Ch PIE1
PSPIE
(1)
ADIE RCIE TXIE SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
98h TXSTA
CSRC TX9 TXEN SYNC —BRGHTRMT 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.
Note 1: Bits PSPIE and PSPIF are reserved on 28-pin devices; always maintain these bits clear.