Symmetricom 5401 Manual De Usuario

PN 8500-0150, Rev. A, May 2005

7

Operating Manual

Operation

Neither the 5401 nor the 5402 have any external manual controls. Signal output amplitude is 
controlled by internal potentiometers, which are located as described in 

. All 

operational control of the DRO is accomplished by means of an RS-232 input/output port.  

The DRO has been equipped with an RS-232 interface using a 13-pin MS type connector 
designated as J14 RS232 on the 5401, and using a DB15 connector designated as J3 on the 
5402. This serial port can be used to communicate with the DRO from a computer or a 'smart 
terminal.' All communication is in the ASCII format. The standard character protocol is 9600 
BAUD, one start bit, eight data bits, none for parity, and one stop bit. 

The connector pin assignments and designations for both connectors are given in 

. 

All communication to the DRO comprises two or three categories of characters. The first 
category is a single character which is always an ASCII $ (Hex 24). This is the 
attention/log-on character. The second category is an ID ASCII character which is a 
command to the unit. The third category (which may or may not be applicable) is a series of 
ASCII data bits to input data into the DRO. Leading zeros must be used where necessary. For 
example, if the number to be input is fifty-two, and if the data field is a four digit number, then 
it must be entered as 0052. 

All command message inputs and response outputs end with Carriage Return (CR), Line 
Feed (LF).

When burst status is on, the unit will not send a response. However, configuration parameters 
can still be changed. 

 shows the functions available. The ASCII character is shown followed by 

its HEX equivalent. Comments pertaining to that specific function are also included for clarity. 

If a mistake is made while inputting new characters (prior to the last character), issuing 
the "$" character will cause a reset, and the new (correct) characters can be input.