PIC16F872 Datasheet, PDF (59/160 Pages) Microchip Technology – 28-Pin, 8-Bit CMOS FLASH Microcontroller

PIC16F872
9.1.2 SLAVE MODE
In Slave mode, the data is transmitted and received as
the external clock pulses appear on SCK. When the
last bit is latched, the interrupt flag bit SSPIF (PIR1<3>)
is set.
While in Slave mode, the external clock is supplied by
the external clock source on the SCK pin. This external
clock must meet the minimum high and low times as
specified in the electrical specifications.
While in SLEEP mode, the slave can transmit/receive
data. When a byte is received, the device will wake-up
from sleep.
Note:
Note:
When the SPI module is in Slave mode
with SS pin control enabled, (SSP-
CON<3:0> = 0100) the SPI module will
reset if the SS pin is set to VDD.
If the SPI is used in Slave mode with
CKE = ’1’, then SS pin control must be
enabled.
FIGURE 9-3: SPI MODE TIMING (SLAVE MODE WITH CKE = 0)
SS (optional)
SCK (CKP = 0)
SCK (CKP = 1)
SDO
SDI (SMP = 0)
SSPIF
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit0
FIGURE 9-4: SPI MODE TIMING (SLAVE MODE WITH CKE = 1)
SS
SCK (CKP = 0)
SCK (CKP = 1)
SDO
SDI (SMP = 0)
SSPIF
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit0
© 1999 Microchip Technology Inc.
Preliminary
DS30221A-page 59