User manual

Chapter 2. Notes concerning the

communication protocol TCP

Access to the different models of the AnaGate product line is always done via the most frequently used

network protocol TCP (Transmission Control Protocol).

TCP is connection-oriented packet-switched transport protocol which is located in layer 4 of the of the

OSI reference model. In princible TCP is an end-to-end connection which allows exchange of data in both

directions at the same time. An end-point is a pair formed of an IP address and a port number and. Such

a pair builds a bidirectional software interface and is called socket.

The AnaGate device offers its functionality as so-called TCP server. It creates a socket with its IP

address and a device-specific port number. On the models with CAN interface(s) a seperate socket with

different port number is created for each existing CAN interface, on every socket up to 5 concurrent client

connections are accepted. The SPI, I2C and Renesas interfaces accept only one concurrent connection at

the same time.

Table 2.1. AnaGate devices and related port numbers

Device Port number

AnaGate I2C, AnaGate Universal Programmer 5000

AnaGate CAN, AnaGate CAN uno 5001

AnaGate CAN duo 5001, 5101

AnaGate CAN quattro 5001, 5101, 5201, 5301

AnaGate SPI, AnaGate Universal Programmer 5002

AnaGate Renesas, AnaGate Universal Programmer 5008

Important

Please ensure that all used ports are set active on the personal computer to grant access to

the AnaGate device. Any existing firewalls are to be configured accordingly.

2.1. Important properties of the network

protocol

In most cases TCP is based on the internet protocol (IP). IP is package-oriented, whereby it is possible that

data packets are lost or the packets can be received in wrong order or perhaps more than once.

TCP eliminates this behaviour and ensures that the the data packets are received in correct order at

the recipient. Is a sent data packet not confirmed by the recipient within a timeout limit, the packet

is sent again. Double packets are recognized at the recipient and are deleted. During connection the

data transmission may be impaired, delayed or completely interrupted. A successful connection do not

guarantee a permanently stable data transmission.

Detection and evaluation of network and line malfunctions can be difficult, if there is only sporadic

communication on the line. How is possible to distinguish between a malfunction on the line or simply

no data from the connected endpoint?