CMV
-
50 Operations Manual
Copyright illunis, LLC 9/20/2019
Page 50
Serial Communi
cation
CMV
-
50
COMMAND DESCRIPTIONS
Read Command Structure
The CMV
-
50 camera parses the sequence byte by byte. An invalid read command,
target , or index will cause the camera to issue a NACK. The Host (the user) will
generate dummy data with a valid checksum then an end. The camera will respond
with an ACK and re
-
send the command with valid data and checksum. If the Host
detects an error, it will re
-
issue the command.
Host {r tt ii 0 0 0 0 cc}, camera issues !
Camera issues {r tt ii data data data data cc} (NOTE no ACK).
Write Command Structure
The CMV
-
50 camera parses the sequence byte by byte. An invalid write command,
target, index, or checksum will cause the camera to issue a NACK; otherwise, the
write sequence will complete and the camera will issue an ACK after the command
has been executed. The camera receives the checksum from the Host.
Host {w tt ii data data data data cc} camera issues !
Error Checking
The CMV
-
50 camera parser is character by character and will respond with an
immediate NACK if any unrecognized command, target, index, or checksum occurs.
Communication Timeouts
The CMV
-
50 camera micro
-
controller uses a hardware watchdog timer that will time
out if the time between bytes are longer than 500ms. When sending command
frames to the camera, the host must not have significant delays between bytes sent.
