GEViCAM GP-151400, Operation Manual

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3.4.1.2 CAN Device Control
CAN (Controller Area Network) is slightly different serial bus using the same technology as RS-485.
As option, we can mount CAN device instead of RS-485 transceiver. CAN protocol must be provided
by user.
3.4.2 Opto-isolated I/O
There are two sets of optically-isolated inputs and outputs (Fig. 23).
With setting of solder jumpers J1 and J2, the IOs can be one input/one
output, two inputs, or two outputs. These IOs are designed for the appli-
cations which need different voltages, used in high surge/noise environ-
ment, the signal isolation from camera body, etc.
Standard setting is one input (D1=J1 open) and one output (D2=J2
short).
For input selection, J1 and J2 jumpers are open, and they are shorted
(solder jumper) for output.
Factory default is open on J1 and short on J2.
3.4.3 Audio CODEC I/O
It has a built-in audio CODEC to handle digital audio via Ethernet. It uses the high speed serial port
(Bulk port 0) to take audio stream. The input can be also used for analog input monitoring (AC cou-
pled) in audio frequency range (10 Hz - 10 KHz) such as the Doppler speedometer, chopped DC level
detection, etc. The audio input and output have no audio amp or speaker driver. Therefore, auxiliary
device may be required.
The GPIO pin assignment is #13 for output, #14 for input. The full function cable uses shield cable for
these pins. The signal is similar to the computer audio IO (AUX input, earphone output).
3.4.4 Temperature Sensor
A temperature sensor is built-in on the GPIO board to monitor internal thermal condition. It is part of
internal I
2
C control (90 XX) and the value can be accessed by reading the register address in the
Camera control port (0). Type “52” (Read) then address “90 00” for the I
2
C temperature sensor. You
will get the data in hexadecimal. The raw data have to be converted to actual
°
C (binary formatted in
2’s complement). The resolution of data output is 9 bit (0.5
°
C resolution) with one sign bit. The data
are in hexadecimal and have to be converted to binary in the 9-bit resolution from MSB in 16-bit.
bit 15 bit 14 bit 13 bit 12 bit 11 bit 10 bit 9 bit 8 bit 7 bit 6-0
Sign bit 2
6
°
C/bit 2
5
°
C/bit 2
4
°
C/bit 2
3
°
C/bit 2
2
°
C/bit 2
1
°
C/bit 2
0
°
C/bit 2
-1
°
C/bit all 0
For example: Hexadecimal Binary Decimal Ta (
°
C) = 1/2 x (Decimal)
0FA 0111 1101 0 250 +125
032 0001 1001 0 50 +25
001 0000 0000 1 1 0.5
000 0000 0000 0 0 0
001* 1111 1111 1 -1 -0.5
370* 1100 1001 0 -110 -55
(Negative temperature conversion is done by complimenting each binary bit and adding 1 and
Sign bit is 1). * These data indicate negative values due to the sign bit of Binary data.
Example: Type “52 a0 00” <Return>. You will see the data of 52 a0 00 00 00 00 50 0D. On the data,
50 Hex is 80 in Decimal. So the temperature is 40
°
C (0D is “ Acknowledge” )
(Note: Refer the related document of MCP9800 for more details.)
GEViCAM Inc
GPIO Board
Fig. 23
W1 GND W2 Video
W3 Cont+ W4 Cont-
W5 Drive- W6 Drive+
(5V)
Table 2