Pleora Technologies iPort NTx-Pro, Руководство по оборудованию

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Copyright © 2010 Pleora Technologies Inc.
Bulk Interface: I2C
The I2C serial interface is a bi-directional serial bus that supports multi-master communication between
many serial-capable devices. The NTx-Pro IP Engine supports these features:
• I2C clock speeds of 100 KHz (standard mode) and 400 kHz (fast mode)
• Direct and indirect addressing
• Burst reads up to 64 kBytes; unlimited burst writes
For detailed timing and important implementation details, see The I2C-Bus Specification, version 2.1,
January 2000 , from Philips Semiconductors (document order number: 9398 393 40011).
For a general description of how I2C works, see http://en.wikipedia.org/wiki/I2C.
I
2
C Signal Nomenclature
IP Engine Signal Generic Signal
BULK0_RX n/a
BULK0_TX SDA
BULK0_CLK SCL
NOTE! I2C pull-ups are not present on the NTx-Pro board. These pull-ups must be provided by the
external user circuitry.
Read and Write Methods
Read and write methods using the I2C protocol with the eBUS SDK are explained below.
eBUS SDK Suite
The eBUS SDK Suite includes a PvIPEngineI2CBus class that allows you to communicate with your
camera using the I2C protocol. Refer to PvIPEngineI2CBus in the
eBUS SDK .
The figure below describes the specific bits transferred between the IP Engine and the camera when
using PvIPEngineI2CBus methods.
S SLAVE ADDR R A
PvIPEngineI2CBus::I2CBurstRead
DATA A DATA A DATA A DATA A P
S SLAVE ADDR W A
PvIPEngineI2CBus::I2CBurstWrite
DATA A DATA A DATA A DATA A P
S SLAVE ADDR W A
PvIPEngineI2CBus::I2CIndirectBurstRead
DATA A DATA A DATA A DATA A P
S SLAVE ADDR W A
PvIPEngineI2CBus::I2CIndirectBurstWrite
DATA A DATA A DATA A DATA A P
Sr OFFSET A SLAVE ADDR R A
OFFSET A
n bytes
n bytes
n bytes
n bytes
A - acknowledge (SDA low)
A - not acknowledge (SDA high)
S - START Condition
P - STOP Condition
Sr - STOP/START or Repeated START Condition
- from master to slave
- from slave to master
W - write (SDA low)
R - read (SDA high)
n - BufferSize