9 Serial command interface definition for DVC-1412
cameras (LVDS and CameraLink Cameras)
9.1 INTRODUCTION
The following is a definition of the serial control interface for the DVC-1310A/1312A/1412
cameras. Serial control is standard within all DVC131X cameras; it can be controlled via a
communication program (such as Windows HyperTerminal) or within a larger program, such as C-
View.
9.2 PHYSICAL DESCRIPTION
The serial control interface is physically designed as a microprocessor-based circuit that is present
on-board the DVC-131X camera. The microprocessor has an on-board UART which
communicates with the serial port of the PC via an RS232 interface chip. The microprocessor is
configured to have two data ports that control the camera modes and the exposure of the camera. In
addition to the data ports, a dual digital-to-analog converter (DAC) is used to control the camera
gain and offset by creating two 0-to-3V analog control voltages. The microprocessor decodes valid
camera commands and creates the user specified combination of the two data ports and the two
analog control voltages.
9.3 COMMUNICATION PROTOCOL
Serial communication protocol: the camera uses a full duplex UART type asynchronous
system, using standard non-return-to-zero (NRZ) format (one start bit, eight data bits, one stop
bit, no parity). The baud rate is fixed at 9600. The character code is based on the ASCII
standard. Character flow protocol: None
Command Syntax: the camera will recognize a command as three command characters,
followed by a space character, followed by an argument that consists of two characters, ended
by the carriage return character.
Query Syntax: the camera will recognize a query as three command characters followed by the
question mark character, then ended by the carriage return character. The camera responds to a
query with three command characters, followed by a space character, followed by an argument
that consists of three characters, then ended by the carriage return character.
Error messages: the camera responds to an erroneous command or query in one of three possible
ways:
ERROR MESSAGE EXPLANATION
E-SYN
The camera cannot understand the command
E-ARG
The camera can understand the command, but the argument is either out-of-
range or not understood e.g. an alpha character embedded in a numeric string
E-XMT
The camera detects a transmission error e.g. buffer overflow, parity o
framing.
E-HRT
The HRT command was issued in a mode in which Hardware Reset is illegal.
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