PIC18F44J50-I Datasheet, PDF (334/562 Pages) Microchip Technology – 28/44-Pin, Low-Power, High-Performance USB Microcontrollers

PIC18F46J50 FAMILY
FIGURE 20-3:
EUSART TRANSMIT BLOCK DIAGRAM
TXxIE
TXxIF
MSb
(8)
Interrupt
TXEN Baud Rate CLK
BRG16
SPBRGHx SPBRGx
Baud Rate Generator
Data Bus
TXREGx Register
8

TSR Register
TX9
TX9D
LSb
0
Pin Buffer
and Control
TRMT
SPEN
TXx pin
FIGURE 20-4:
Write to TXREGx
BRG Output
(Shift Clock)
TXx (pin)
TXxIF bit
(Transmit Buffer
Reg. Empty Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
ASYNCHRONOUS TRANSMISSION
Word 1
Start bit
bit 0
1 TCY
bit 1
Word 1
Word 1
Transmit Shift Reg
bit 7/8 _{Stop bit}
FIGURE 20-5:
ASYNCHRONOUS TRANSMISSION (BACK-TO-BACK)
Write to TXREGx
BRG Output
(Shift Clock)
TXx (pin)
TXxIF bit
(Interrupt Reg. Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
Word 1
Word 2
1 TCY
Start bit
bit 0
Word 1
Transmit Shift Reg.
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.
DS39931D-page 334
 2011 Microchip Technology Inc.