PIC18F23K20 Datasheet, PDF (250/420 Pages) Microchip Technology – 28/40/44-Pin Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology

PIC18F2XK20/4XK20
18.4.1.5 Synchronous Master Transmission
Set-up:
1. Initialize the SPBRGH, SPBRG register pair and
the BRGH and BRG16 bits to achieve the
desired baud rate (see Section 18.3 “EUSART
Baud Rate Generator (BRG)”).
2. Enable the synchronous master serial port by
setting bits SYNC, SPEN and CSRC. Set the
TRIS bits corresponding to the RX/DT and
TX/CK I/O pins.
3. Disable Receive mode by clearing bits SREN
and CREN.
4. Enable Transmit mode by setting the TXEN bit.
5. If 9-bit transmission is desired, set the TX9 bit.
6. If interrupts are desired, set the TXIE, GIE and
PEIE interrupt enable bits.
7. If 9-bit transmission is selected, the ninth bit
should be loaded in the TX9D bit.
8. Start transmission by loading data to the TXREG
register.
FIGURE 18-10: SYNCHRONOUS TRANSMISSION
RX/DT
pin
bit 0
bit 1
bit 2
bit 7
bit 0
bit 1
bit 7
Word 1
Word 2
TX/CK pin
(SCKP = 0)
TX/CK pin
(SCKP = 1)
Write to
TXREG Reg
TXIF bit
(Interrupt Flag)
Write Word 1
TRMT bit
Write Word 2
TXEN bit ^{‘1’}
‘1’
Note:
Sync Master mode, SPBRG = 0, continuous transmission of two 8-bit words.
FIGURE 18-11: SYNCHRONOUS TRANSMISSION (THROUGH TXEN)
RX/DT pin
bit 0
bit 1
bit 2
bit 6
bit 7
TX/CK pin
Write to
TXREG reg
TXIF bit
TRMT bit
TXEN bit
DS41303B-page 248
Advance Information
© 2007 Microchip Technology Inc.