3.2.1. How to test PC side loopback

3.2.1. How to test PC side loopback

 

Figure 3.6 RS-232C communication setting dialog box

 

(1)   In order to test if RS-232C connection is normal, open communication setting dialog box first and press  button to connect the communication. When pressing  button, RS-232C communication test dialog box will be displayed as follows.

 

Figure 3.7 RS-232C communication test dialog box

 

 

Table 3‑1 RS-232C communication test dialog box

Transmission group box	Transmission button	It transfers a string inputted in transmission edit box to RS-232C. (Only front 500 byte will be transmitted.)
	Delete all button	It deletes all strings in transmission edit box.
	Edit box	This is a location for recording a string to be transmitted. In case of text file loopback test, it displays a string to be transferred.
Reception group box	Delete all button	It deletes all strings in reception edit box.
	Edit box	It displays a strong which is being received to RS-232C.
Test result edit box		It displays the result of text file loopback test. Transmitted bytes, received bytes, conformity option, location of unconformity occurred and the string will be displayed.
Automatic check box		It selects whether text file loopback test will be repeated automatically or not.
Text file loopback test button		It executes text file loopback test. It reads long string data from internal text file, transmits it to RS-232C and test conformity option by comparing it with data received by loopback. Transmitted and received data will be displayed on edit box separately.
Close button		It closes RS-232C communication test dialog box.

 

 

(2)   A method of confirming if COM port selected from serial ports of PC is running normally is as follows: Short No.2 pin and No.3 pin first from the connector of cable attached to COM port of PC as [Figure 3.8].

 

Figure 3.8 PC side transmission and reception short

 

 

(3)   When pressing text file loopback test button, internal text file will be transmitted and received, and the contents of text file will be displayed on edit box. If it is displayed as [Figure 3.9], it is normal

 

Figure 3.9 text file loopback test

 

(4)   The conclusions according to test result are indicated [Table 3-2] below.

 

Table 3‑2 PC side text file loopback test result

Result	Conclusion  (Reasons which can be presumed)
Transmitted data is displayed on reception edit box and test result is displayed as 100% Matched!	COM port of PC is running normally.
There is no data displayed on reception edit box.	- Cable is disconnected. - Cable is connected to wrong COM port of PC. - COM port failure of PC - No. 2 pin and No. 3 pin are not shorted. - Setting error or fault of USB-Serial product (If used)
Partially damaged string rather than received data is displayed on reception edit box.	- Transmission and reception functions of COM port of PC are partially faulty. H/W failure needs to be checked. - Fault or insufficient capacity of USB-Serial product (if used).

 

(5)   A method of confirming if serial communication connection with Robot controller is normal is as follows: Connect COM port of PC and robot controller with serial communication cable first as [Figure 3.10].

 

Figure 3.10 RS-232C connection between PC and controller

 

(6)   Enter 『[F2]: System』→ 『2: Control parameter』→ 『3: Serial port』 → 『1: Serial port #1』(or, 『2: Serial port #2』) screen from teach pendant of robot controller, set communication parameter to be equal with PC side and set “Echo” as <Enable> as [Figure 3.11].

 

 

Figure 3.11 Setting serial port echo as “Enable”

 

(7)   When pressing text file loopback test button, internal text file will be transmitted and received, and its contents will be displayed on edit box. The conclusion according to the test result is indicated [Table 3-3] below.

 

Table 3‑3 PC - controller text file loopback test result

Result	Conclusion (Reasons which can be presumed)
Transmitted data is displayed on reception edit box and test result is displayed as 100% Matched!	COM port of PC is running normally.
There is no data displayed on reception edit box.	- Cable is disconnected. - Cable is connected to wrong COM port of PC. - COM port failure of PC - No. 2 pin and No. 3 pin are not shorted. - Setting error or fault of USB-Serial product (If used)
Partially damaged string rather than received data is displayed on reception edit box.	- Transmission and reception functions of COM port of PC are partially faulty. H/W failure needs to be checked. - Fault or insufficient capacity of USB-Serial product (if used).

 

(8)   After testing, restore “Echo” setting on teach pendant serial port screen as <Disable> again.