PIC18LF452-I/PT Microchip Technology Inc., PIC18LF452-I/PT Datasheet - Page 133

• Manufacturer Part Number: PIC18LF452-I/PT
• Description: 44 PIN, 32 KB FLASH, 1536 RAM, 34 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18LF452-I/PT

• A/d Inputs: 8-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 10 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 36
• Interface: I2C/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 44-pin TQFP
• Programmable Memory: 32K Bytes
• Ram Size: 1.5K Bytes
• Speed: 40 MHz
• Timers: 1-8-bit, 3-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

15.3.6
In Slave mode, the data is transmitted and received as
the external clock pulses appear on SCK. When the
last bit is latched, the SSPIF interrupt flag bit 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.
15.3.7
The SS pin allows a Synchronous Slave mode. The
SPI must be in Slave mode with SS pin control enabled
(SSPCON1<3:0> = 04h). The pin must not be driven
low for the SS pin to function as an input. The Data
Latch must be high. When the SS pin is low, transmis-
sion and reception are enabled and the SDO pin is
driven. When the SS pin goes high, the SDO pin is no
FIGURE 15-4:
SS
SCK
(CKP = 0
CKE = 0)
SCK
(CKP = 1
CKE = 0)
Write to
SSPBUF
SDO
SDI
(SMP = 0)
Input
Sample
(SMP = 0)
SSPIF
Interrupt
Flag
SSPSR to
SSPBUF
2002 Microchip Technology Inc.
SLAVE MODE
SLAVE SELECT
SYNCHRONIZATION
SLAVE SYNCHRONIZATION WAVEFORM
bit7
bit7
bit6
longer driven, even if in the middle of a transmitted
byte, and becomes a floating output. External pull-up/
pull-down resistors may be desirable, depending on the
application.
When the SPI module resets, the bit counter is forced
to 0. This can be done by either forcing the SS pin to a
high level or clearing the SSPEN bit.
To emulate two-wire communication, the SDO pin can
be connected to the SDI pin. When the SPI needs to
operate as a receiver the SDO pin can be configured as
an input. This disables transmissions from the SDO.
The SDI can always be left as an input (SDI function),
since it cannot create a bus conflict.
Note 1: When the SPI is in Slave mode with SS
2: If the SPI is used in Slave mode with CKE
pin control enabled (SSPCON<3:0> =
0100), the SPI module will reset if the SS
pin is set to V
set, then the SS pin control must be
enabled.
bit7
bit7
PIC18FXX2
DD
.
Next Q4 cycle
after Q2
DS39564B-page 131
bit0
bit0