PIC18F2550-I/SP Microchip Technology Inc., PIC18F2550-I/SP Datasheet - Page 226

• Manufacturer Part Number: PIC18F2550-I/SP
• Description: Microcontroller; 32 KB Flash; 2048 RAM; 256 EEPROM; 24 I/O; 28-Pin-SPDIP
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F2550-I/SP

• A/d Inputs: 10-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 12 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 23
• Interface: I2C/SPI/USART/USB
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 28-pin SPDIP
• Programmable Memory: 32K Bytes
• Ram Size: 2K Bytes
• Speed: 48 MHz
• Timers: 1-8-bit, 3-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

PIC18F2455/2550/4455/4550
19.4.7.1
Clock arbitration occurs when the master, during any
receive, transmit or Repeated Start/Stop condition,
deasserts the SCL pin (SCL allowed to float high).
When the SCL pin is allowed to float high, the Baud
Rate Generator (BRG) is suspended from counting
until the SCL pin is actually sampled high. When the
FIGURE 19-20:
DS39632C-page 224
Clock Arbitration
SDA
SCL
BRG
Value
BRG
Reload
BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION
03h
DX
SCL deasserted but slave holds
SCL low (clock arbitration)
02h
SCL is sampled high, reload takes
place and BRG starts its count
01h
Preliminary
BRG decrements on
Q2 and Q4 cycles
00h (hold off)
DX – 1
SCL pin is sampled high, the Baud Rate Generator is
reloaded with the contents of SSPADD<6:0> and
begins counting. This ensures that the SCL high time
will always be at least one BRG rollover count in the
event that the clock is held low by an external device
(Figure 19-20).
SCL allowed to transition high
03h
© 2006 Microchip Technology Inc.
02h