Tektronix TPS2012B, User Manual

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Communications (RS-232, Centronics, and RS-232/USB)
Transferring Binary Data To use the RS-232 port to transfer binary data to the oscilloscope, set up the
interface as follows:
Use hardware fl agging (RTS/CTS) whenever possible. Hardware fl agging
guarantees no data loss.
All eight bits of binary data contain meaningful information. To make sure
that all eight bits are received or transmitted, con
fi gure the external RS-232
device to receive and transmit eight-bit characters (set the RS-232 word
length to eight bits).
Reporting RS-232 I/O
Errors
Errors are reported when there is a problem with parity, framing, or input/output
buffer overruns. To report errors, the oscilloscope posts an event code. When an
error occurs, the oscilloscope discards all input and output and waits for a new
command.
Checking Command Status If you want to check the status of each command sent, append an *STB? query
after every command and read the response string.
Processing Break Signals When the oscilloscope senses a break signal on the RS-232 port, it returns the
three character string DCL followed by the end-of-line terminator. Internally, the
oscilloscope acts as if it received a GPIB <DCL> command (device clear), causing
the oscilloscope to erase the contents of the input and output buffers and then wait
for a new command. Break signals do not change oscilloscope settings or stored
data and do not interrupt front-panel operation or nonprogrammable functions.
If a break signal is sent in the middle of a character stream, several characters
immediately preceding or following the break can be lost. The controller waits
until it receives the three character string DCL and the end of line terminator
string before sending more characters.
RS-232 Connector Pinout
Diagram
The next fi gure shows the pin numbering and signal assignments for the RS-232
connector.
TPS2000B Series Digital Oscilloscope User Manual 77