Cheetah KAC Camera User Manual | Camera Link (CLF) Interface
October 1, 2019
Page
38
of
135
Rev 7.2
3.1.4 Read Operation
In order to read from any given camera register, a sequence of 3 bytes should be sent
to the camera. If there is no error the camera returns 5 bytes – one byte acknowledge
for the read command <Ack> and four bytes of data <DD> <DD> <DD> <DD> . During
read operation the camera does not return an error or <Nac>. The only exception is
the case of invalid command. If the user specifies a wrong address, the camera returns
acknowledge <06> and four bytes of data
<
00
> <
00
> <
00
> <
00
>.
Read from camera (3 Bytes) : <Read_Cmd> <
Address
>
1
st
byte: 0x52 (Read Command)
2
nd
byte: <Register Address_High>
MSB
3
rd
byte: <Register Address_Low>
LSB
The camera returns (5 bytes): <ACK> <
Data
>
1
st
byte: 0x06 (Acknowledge)
2
nd
byte: <
Register Data Byte 4
> MSB
3
rd
byte: <
Register Data Byte 3
> …
5
th
byte: <
Register Data Byte 2
> …
6
th
byte: <
Register Data Byte 1
> LSB
52
04
10
11
22
33
44
06
Rd_Cmd
Addr
Data
Ack
Rx
Tx
Figure 28: Normal read cycle.
Example
: Read from camera register address 0x0410:
Camera Read Command:
<0x52> <
04
> <
10
>
Camera returns register data payload value 0x11223344:
Register data
<0x06> <
11
> <
22
> <
33
> <
44
>
