
PIC18F2450/4450
2006 Microchip Technology Inc.
Advance Information
DS39760A-page 165
FIGURE 15-7:
ASYNCHRONOUS RECEPTION
TABLE 15-6:
REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Start
bit
bit 7/8
bit 1
bit 0
bit 7/8
bit 0
Stop
bit
Start
bit
Start
bit
bit 7/8
Stop
bit
RX (pin)
Rcv Buffer Reg
Rcv Shift Reg
Read Rcv
Buffer Reg
RCREG
RCIF
(Interrupt Flag)
OERR bit
CREN
Word 1
RCREG
Word 2
RCREG
Stop
bit
Note:
This timing diagram shows three words appearing on the RX input.
The RCREG (Receive Buffer) is read after the third word
causing the OERR (Overrun) bit to be set.
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Reset
Values
on page
INTCON
GIE/GIEH PEIE/GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
PIR1
—
ADIF
RCIF
TXIF
—
CCP1IF
TMR2IF
TMR1IF
PIE1
—
ADIE
RCIE
TXIE
—
CCP1IE
TMR2IE
TMR1IE
IPR1
—
ADIP
RCIP
TXIP
—
CCP1IP
TMR2IP
TMR1IP
RCSTA
SPEN
RX9
SREN
CREN
ADDEN
FERR
OERR
RX9D
RCREG
EUSART Receive Register
TXSTA
CSRC
TX9
TXEN
SYNC
SENDB
BRGH
TRMT
TX9D
BAUDCON
ABDOVF
RCIDL
—
SCKP
BRG16
—
WUE
ABDEN
SPBRGH
EUSART Baud Rate Generator Register High Byte
SPBRG
EUSART Baud Rate Generator Register Low Byte
Legend: — = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous reception.