PIC18F6621-I/PT Microchip Technology Inc., PIC18F6621-I/PT Datasheet - Page 203

• Manufacturer Part Number: PIC18F6621-I/PT
• Description: 64 PIN, 64 KB FLASH, 3840 RAM, 52 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F6621-I/PT

• A/d Inputs: 12-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 10 MIPS
• Eeprom Memory: 1024 Bytes
• Input Output: 54
• Interface: I2C/SPI/UART/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 64-pin TQFP
• Programmable Memory: 64K Bytes
• Ram Size: 3.8K Bytes
• Speed: 40 MHz
• Timers: 2-8-bit, 3-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

18.4.8
To initiate a Start condition, the user sets the Start
condition enable bit, SEN (SSPCON2<0>). If the SDA
and SCL pins are sampled high, the Baud Rate
Generator
SSPADD<6:0> and starts its count. If SCL and SDA are
both sampled high when the Baud Rate Generator
times out (T
of the SDA being driven low while SCL is high is the
Start condition and causes the S bit (SSPSTAT<3>) to
be set. Following this, the Baud Rate Generator is
reloaded with the contents of SSPADD<6:0> and
resumes its count. When the Baud Rate Generator
times out (T
automatically cleared by hardware, the Baud Rate
Generator is suspended, leaving the SDA line held low
and the Start condition is complete.
FIGURE 18-19:
 2005 Microchip Technology Inc.
I
CONDITION TIMING
BRG
BRG
2
is
C MASTER MODE START
), the SDA pin is driven low. The action
), the SEN bit (SSPCON2<0>) will be
reloaded
Write to SEN bit occurs here
FIRST START BIT TIMING
with
SDA
SCL
the
contents
PIC18F6525/6621/8525/8621
SDA = 1,
SCL = 1
T
BRG
of
Set S bit (SSPSTAT<3>)
T
S
BRG
At completion of Start bit,
hardware clears SEN bit
18.4.8.1
If the user writes the SSPBUF when a Start sequence
is in progress, the WCOL is set and the contents of the
buffer are unchanged (the write doesn’t occur).
and sets SSPIF bit
Note:
Note:
T
Write to SSPBUF occurs here
BRG
If at the beginning of the Start condition,
the SDA and SCL pins are already sam-
pled low, or if during the Start condition, the
SCL line is sampled low before the SDA
line is driven low, a bus collision occurs,
the Bus Collision Interrupt Flag, BCLIF, is
set, the Start condition is aborted and the
I
Because queueing of events is not
allowed, writing to the lower 5 bits of
SSPCON2 is disabled until the Start
condition is complete.
2
1st bit
C module is reset into its Idle state.
WCOL Status Flag
T
BRG
2nd bit
DS39612B-page 201