PIC18F-LF1XK50 Datasheet, PDF (202/420 Pages) Microchip Technology – 20-Pin USB Flash Microcontrollers

PIC18F/LF1XK50
16.4.1.5 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 16.3 “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 16-10: 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 16-11: 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
DS41350E-page 202
Preliminary
 2010 Microchip Technology Inc.