
2002 Microchip Technology Inc.
Preliminary
DS30485A-page 133
PIC18FXX39
16.3.8
SLEEP OPERATION
In Master mode, all module clocks are halted and the
transmission/reception will remain in that state until the
device wakes from SLEEP. After the device returns to
Normal mode, the module will continue to transmit/
receive data.
In Slave mode, the SPI transmit/receive shift register
operates asynchronously to the device. This allows the
device to be placed in SLEEP mode and data to be
shifted into the SPI transmit/receive shift register.
When all 8 bits have been received, the MSSP interrupt
flag bit will be set and if enabled, will wake the device
from SLEEP.
16.3.9
EFFECTS OF A RESET
A RESET disables the MSSP module and terminates
the current transfer.
16.3.10
BUS MODE COMPATIBILITY
standard SPI modes and the states the CKP and CKE
control bits.
TABLE 16-1:
SPI BUS MODES
There is also an SMP bit which controls when the data
is sampled.
TABLE 16-2:
REGISTERS ASSOCIATED WITH SPI OPERATION
Standard SPI Mode
Terminology
Control Bits State
CKP
CKE
0, 0
0
1
0, 1
0
1, 0
1
1, 1
1
0
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
All Other
RESETS
INTCON
GIE/GIEH
PEIE/
GIEL
TMR0IE
INT0IE
RBIE
TMR0IF
INT0IF
RBIF
0000 000x
0000 000u
PIR1
PSPIF(1)
ADIF
RCIF
TXIF
SSPIF
—
TMR2IF
TMR1IF
0000 0000
PIE1
PSPIE(1)
ADIE
RCIE
TXIE
SSPIE
—
TMR2IE
TMR1IE
0000 0000
IPR1
PSPIP(1)
ADIP
RCIP
TXIP
SSPIP
—
TMR2IP
TMR1IP
0000 0000
TRISC
TRISC7
TRISC6
TRISC5
TRISC4
TRISC3
*
TRISC0
1111 1111
SSPBUF
Synchronous Serial Port Receive Buffer/Transmit Register
xxxx xxxx
uuuu uuuu
SSPCON
WCOL
SSPOV
SSPEN
CKP
SSPM3
SSPM2
SSPM1
SSPM0
0000 0000
TRISA
—
PORTA Data Direction Register
-111 1111
SSPSTAT
SMP
CKE
D/A
P
S
R/W
UA
BF
0000 0000
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by the MSSP in SPI mode.
* Reserved bits; do not modify.
Note 1: The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices; always maintain these bits clear.