1 communication protocol, 1 i/o status monitoring, Figure 6.2. hellodevice i/o communication protocol – SENA HD1100 User Manual
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Starter Kit and User Manual for the HelloDevice 1100
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Chapter 6.1 will describe the HelloDevice communication protocol; Chapter 6.2 will describe the I/O demo
board and how to implement user hardware that complies with the HelloDevice I/O interface.
6.1 Communication Protocol
In order to perform remote I/O control on the Internet, the Internet socket interface should be implemented on
the user PC for Internet communication with the HelloDevice. The socket interface can be implemented with:
§ C language-based socket program,
§ Or, Java applet running on the Web.
The Internet socket interface for communication with the HelloDevice should be implemented according to the
TCP/IP protocol. This sends the I/O control command to the current IP address and to the TCP port number 6001.
The HelloDevice interprets the commands to control the I/O device connected to the actual HelloDevice. The
Table 6.1 summarizes the communication commands and response that are sent between the socket interface and
the HelloDevice.
Direction
Operation Type
Communication Packet
User PC
HelloDevice
I/O Get Command
è
Monitoring I/O Status
I/O Get Command Response
ç
Output Control
Output Set Command
è
Table 6.1. List of communication commands/responses for HelloDevice I/O control
6.1.1 I/O Status Monitoring
I/O status is monitored by a command and its response Commands are sent from the socket interface of the user
PC to the HelloDevice in order to read the HelloDevice I/O status. The Figure 6.2 shows the table used to
interpret the monitoring command and its response, and output I/O contact point.
Number of Byte
Type
1
2
3
4
Command to monitor the I/O status
0x75
Response to I/O status monitoring
Input Contact Point
Status
Output Contact Point
Status
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Input Contact Point MSB
Input Contact Point LSB
Output Contact Point MSB
Output Contact Point LSB
Input Contact Point Status
Output Contact
Point Status
Figure 6.2. HelloDevice I/O communication protocol