PIC18F1220_07 Datasheet, PDF (144/308 Pages) Microchip Technology – 18/20/28-Pin High-Performance, Enhanced Flash Microcontrollers with 10-bit A/D and nanoWatt Technology

PIC18F1220/1320
FIGURE 16-4:
Write to TXREG
BRG Output
(Shift Clock)
RB1/AN5/TX/
CK/INT1 (pin)
TXIF bit
(Interrupt Reg. Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
ASYNCHRONOUS TRANSMISSION (BACK TO BACK)
Word 1
Word 2
1 TCY
Start bit
Word 1
Transmit Shift Reg.
bit 0
1 TCY
bit 1
Word 1
bit 7/8 Stop bit
Start bit
bit 0
Word 2
Word 2
Transmit Shift Reg.
Note: This timing diagram shows two consecutive transmissions.
TABLE 16-5: REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
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
INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 0000 000x 0000 000u
PIR1
—
ADIF
RCIF TXIF
— CCP1IF TMR2IF TMR1IF -000 -000 -000 -000
PIE1
—
ADIE
RCIE TXIE
— CCP1IE TMR2IE TMR1IE -000 -000 -000 -000
IPR1
—
ADIP
RCIP TXIP
— CCP1IP TMR2IP TMR1IP -111 -111 -111 -111
RCSTA
SPEN
RX9
SREN CREN ADDEN FERR OERR RX9D 0000 -00x 0000 -00x
TXREG EUSART Transmit Register
0000 0000 0000 0000
TXSTA
CSRC
TX9
TXEN SYNC SENDB BRGH TRMT TX9D 0000 0010 0000 0010
BAUDCTL
—
RCIDL
—
SCKP BRG16
—
WUE ABDEN -1-1 0-00 -1-1 0-00
SPBRGH Baud Rate Generator Register High Byte
0000 0000 0000 0000
SPBRG Baud Rate Generator Register Low Byte
0000 0000 0000 0000
Legend: x = unknown, – = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous transmission.
DS39605F-page 142
© 2007 Microchip Technology Inc.