EPC901 Datasheet, PDF (17/37 Pages) Espros Photonics corp – CCD line sensor 1024x1 pixel

10. I2C interface
The epc901 supports the following functions by using the I2C interface:
■ Fast I2C (400 kBit/s)
■ 7-bit addressing
■ Slave (epc901 is always the slave)
■ Supported functions are software reset, read, write, read the device address
Clock stretching and other uses of I2C bus are not supported. The register list which can be accessed by the I2C interface are listed in
section 10.3. All registers can be accessed directly except the test mode registers.
10.1. I2C communication
10.1.1. Device addressing
The MSBs of the device address are fixed to '001' internally, the LSBs A3 to A0 can be set by the two ternary input pins CS0 and CS1.
L
CS1 M
H
L
0000
0100
1100
CS0
M
0001
0101
1101
H
0011
0111
1111
The LSB of the device addressing is used to select the communication direction:
0
0
1 A₃ A₂ A₁ A₀ 0
Write access
The bus protocol in the following sections uses the following notation:
Symbol
S
P
A
N
Shaded
Unshaded
Function
START
STOP
ACK
NACK
Master
Slave (epc901
10.1.2. Single-byte write
Device address
S0 0 1
0 A Register address A
Data
AP
10.1.3. Multi-byte write
During a multi-byte write operation the master transmits the device address and the address of the first register to be written. All subse -
quent bytes until STOP are interpreted as write data packets.
Device address
S001
0 A Register address A
Write data 0
A
Write data 1
A
Write data n
AP
Registers reside in a non-consecutive address space. Writing to a unused address will fail silently (no error feedback).
© 2016 ESPROS Photonics Corporation
Characteristics subject to change without notice
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Datasheet_epc901-V5.6
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