Serial Analyser

The Status Bar

The following shows a typical status bar display for a cursor located at the 218th item.

 

 

The first item #218 is the index number of the character. It simply follows the cursor position. The second item is the character time stamp. This is the number of second since the first character was received. The next field shows either DTE or DCE depending on which channel the character was received. The DCE is the character received on pin 3 of a 9 pin RS232 D connector, while DTE is from pin 2. The next item is the ASCII value of the character. In this case it is the letter 'C'. If the character is not between 32 and 127 then this field is not shown. The hex field shows the hexidecimal value of the character. The binary field shows its binary value.

Data Errors

On MS windows if there are errors associated with the received character the status bar will show the type of error. These can be parity error, framing error or overrun error. An overrun error is not a true communication error but rather an indication that the operating system has failed to receive all the data.

On Linux the operating system quietly replaces the bad character with a null character. This means that error highlighting can not work. Also note that parity checking is not available on all PC serial port's hardware.

Modem Status

The modem status are shown on the right side of the status bar. When the signal level is active it is shown with its label. Note the modem status signals are sampled as close as possible to the moment a character is received.

 

 

The signals are

Description

Label

Pin(D9)

Data Terminal Ready

DTR

4

Data Set Ready

DSR

6

Request to Send

RTS

7

Clear to Send

CTS

8

Data Carry Detected

DCD

1

Incoming call

RING

9

Selected mode

When a range of received characters is selected the status bar will show the index number of the beginning of the range and the end. It also shows the time stamps and the time difference.

 

 

This example show the selection range from item 218 to 244 with a time span of 0.655 seconds

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