PIC18F6490-E/PT Microchip Technology, PIC18F6490-E/PT Datasheet - Page 188

• Manufacturer Part Number: PIC18F6490-E/PT
• Description: IC PIC MCU FLASH 16KX16 64TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F6490-E/PT

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, LCD, POR, PWM, WDT
• Number Of I /o: 50
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 64-TFQFP
• For Use With: DM163028 - BOARD DEMO PICDEM LCD
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

PIC18F6390/6490/8390/8490
15.4.9
A Repeated Start condition occurs when the RSEN bit
(SSPCON2<1>) is programmed high and the I
module is in the Idle state. When the RSEN bit is set,
the SCL pin is asserted low. When the SCL pin is
sampled low, the Baud Rate Generator is loaded with
the contents of SSPADD<5:0> and begins counting.
The SDA pin is released (brought high) for one Baud
Rate Generator count (T
Generator times out, if SDA is sampled high, the SCL
pin will be deasserted (brought high). When SCL is
sampled high, the Baud Rate Generator is reloaded
with the contents of SSPADD<6:0> and begins count-
ing. SDA and SCL must be sampled high for one T
This action is then followed by assertion of the SDA pin
(SDA = 0) for one T
this, the RSEN bit (SSPCON2<1>) will be automatically
cleared and the Baud Rate Generator will not be
reloaded, leaving the SDA pin held low. As soon as a
Start condition is detected on the SDA and SCL pins,
the S bit (SSPSTAT<3>) will be set. The SSPIF bit will
not be set until the Baud Rate Generator has timed out.
FIGURE 15-20:
DS39629C-page 186
I
START CONDITION TIMING
2
C MASTER MODE REPEATED
Falling edge of ninth clock,
BRG
REPEAT START CONDITION WAVEFORM
SDA
SCL
while SCL is high. Following
BRG
). When the Baud Rate
end of Xmit
Write to SSPCON2
occurs here.
SDA = 1,
SCL (no change).
2
C logic
BRG
T
SDA = 1,
SCL = 1
.
BRG
T
BRG
Immediately following the SSPIF bit getting set, the user
may write the SSPBUF with the 7-bit address in 7-bit
mode, or the default first address in 10-bit mode. After
the first 8 bits are transmitted and an ACK is received,
the user may then transmit an additional eight bits of
address (10-bit mode) or 8 bits of data (7-bit mode).
15.4.9.1
If the user writes the SSPBUF when a Repeated Start
sequence is in progress, the WCOL is set and the
contents of the buffer are unchanged (the write doesn’t
occur).
Note:
Note 1: If RSEN is programmed while any other
Sr = Repeated Start
T
BRG
2: A bus collision during the Repeated Start
At completion of Start bit,
hardware clears RSEN bit
Set S (SSPSTAT<3>)
and sets SSPIF
Because queueing of events is not
allowed, writing of the lower 5 bits of
SSPCON2 is disabled until the Repeated
Start condition is complete.
Write to SSPBUF occurs here
event is in progress, it will not take effect.
condition occurs if:
• SDA is sampled low when SCL goes
• SCL goes low before SDA is
WCOL Status Flag
T
from low-to-high.
asserted low. This may indicate that
another master is attempting to
transmit a data ‘1’.
BRG
1st bit
T
BRG
© 2007 Microchip Technology Inc.