Datasheet

 2010-2012 Microchip Technology Inc. DS41419D-page 325
PIC16(L)F1824/1828
26.4.2.3 EUSART Synchronous Slave
Reception
The operation of the Synchronous Master and Slave
modes is identical (Section 26.4.1.5 “Synchronous
Master Reception”), with the following exceptions:
• Sleep
• CREN bit is always set, therefore the receiver is
never Idle
• SREN bit, which is a “don’t care” in Slave mode
A character may be received while in Sleep mode by
setting the CREN bit prior to entering Sleep. Once the
word is received, the RSR register will transfer the data
to the RCREG register. If the RCIE enable bit is set, the
interrupt generated will wake the device from Sleep
and execute the next instruction. If the GIE bit is also
set, the program will branch to the interrupt vector.
26.4.2.4 Synchronous Slave Reception
Setup:
1. Set the SYNC and SPEN bits and clear the
CSRC bit.
2. Clear the ANSEL bit for both the CK and DT pins
(if applicable).
3. If interrupts are desired, set the RCIE bit of the
PIE1 register and the GIE and PEIE bits of the
INTCON register.
4. If 9-bit reception is desired, set the RX9 bit.
5. Set the CREN bit to enable reception.
6. The RCIF bit will be set when reception is
complete. An interrupt will be generated if the
RCIE bit was set.
7. If 9-bit mode is enabled, retrieve the Most
Significant bit from the RX9D bit of the RCSTA
register.
8. Retrieve the eight Least Significant bits from the
receive FIFO by reading the RCREG register.
9. If an overrun error occurs, clear the error by
either clearing the CREN bit of the RCSTA
register or by clearing the SPEN bit which resets
the EUSART.
TABLE 26-10: SUMMARY OF REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE
RECEPTION
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Register
on Page
APFCON0 RXDTSEL
SDOSEL
(1)
SSSEL
(1)
— T1GSEL TXCKSEL — — 122
BAUDCON
ABDOVF RCIDL —SCKPBRG16 — WUE ABDEN
310
INTCON GIE PEIE
TMR0IE INTE IOCIE TMR0IF INTF IOCIF
93
PIE1
TMR1GIE ADIE RCIE TXIE SSP1IE CCP1IE TMR2IE TMR1IE
94
PIR1
TMR1GIF ADIF RCIF TXIF SSP1IF CCP1IF TMR2IF TMR1IF
97
RCREG EUSART Receive Data Register
304*
RCSTA SPEN
RX9 SREN CREN ADDEN FERR OERR RX9D
309
TXSTA CSRC TX9 TXEN SYNC
SENDB BRGH TRMT TX9D
308
Legend: — = unimplemented location, read as ‘0’. Shaded cells are not used for synchronous slave reception.
* Page provides register information.
Note 1: PIC16(L)F1824 only.