13
DB-9 pin
Name
Note
1
2
3
4
5
6
7
8
9
-
TXD
RXD
-
GND
-
RTS
CRS
-
-
Transmit Data
Receive Data
-
Signal ground
-
Request to Send
Clear to send
-
*Note: Use a Null-modem or cross over cable (pin 2 and 3 switched) in order to communicate with instrument. When
transmitting large files via RS232, highest baud rate setting of 38400 is recommended, and number of data points of
transfer at any instance should not exceed 1,000,000 points. If 4,000,000 points are required, multiple transfers are
recommended; each time transferring 100,000 points. For optimal speed in transferring large files, GPIB interface is
recommended using block transfer (see Programming Section of this manual).
2.9.1 Communication Speed Chart
The 4076 and 4079 have the capabilities of generating large arbitrary waveforms with up to 4,000,000 points. Due
to this nature, the time it takes to transmit these large waveforms may vary depending on the baudrate and cable used
for RS232 interface. As a general reference, provided below is a chart that shows the approximate amount of time it
takes to download or send the waveforms of the indicated sizes at the rated baudrate speed.
Number of data pts.
Baudrates (bps)
400,000 points
1,000,000 points
38400
~30 mins
(sending)
~15 mins
(receiving)
~1hr (sending)
~30mins (receiving)
2.10 RS-232 Configuration
The instrument use
8 data bits, 1 stop bit, no parity
and baud rate selectable from 2400 to 38.4K (2400, 4800,
9600, 19200, 38400). By default, the instrument is set at
9600-8-N-1
.
When the instrument is in remote mode, it will display the following screen:
This screen comes up whenever there is a transmission process, be it sending or receiving. To return to local mode
and exit this screen, simply press any front panel keys. Only do this when nothing is being transmitted or received
from a connected PC. In the case where a large waveform is being transmitted, please allow
AT LEAST
15
seconds or more after the PC software or program has finished sending
BEFORE
pressing a key to return to local
mode. The instrument requires this time to completely finish generating/transmitting the waveform.
