Advent Instruments Inc.
1. Getting Started
1.3.1 Serial RS-232 Port
The AI-7280 serial port operates at one of the following baud rates: 9600, 19200, 38400,
57600, and 115200. The serial format is fixed at 8 data bits, 1 stop bit, and no parity.
Flow control is not used (either hardware or software).
Upon a power up or reset, the baud rate is set to 9600 bps. It may be changed to one of
the other supported baud rates by writing to the HAL property (Comm.Baud).
If the AI-7280 detects a line break (at least 11 consecutive space bits), it resets the baud
rate back to the default value of 9600 bps and flushes any unprocessed commands from
its internal buffer. When attempting to communicate with the AI-7280 for the first time,
it is good practice to first send a line break, which ensures the baud rate is set to 9600
baud. Once communication is established, the baud rate may be set higher in order to
improve throughput.
The rear panel 9 pin RS-232 connector is configured as a DCE (Data Communications
Equipment) port. As such, no cross over cable is required when making a connection to a
standard PC serial port. A minimum of three wires are required to make a serial
connection. They are TX Data (pin 2), RX Data (pin 3), and Ground (pin 5). The AI-
7280 can monitor the PC's RTS (pin 7) signal and control the state of the CTS (pin 8)
signal, but does not use them to communicate. The DSR (pin 6) and DTR (pin 4)
connections are internally tied together. Pins (1 and 9) have no internal connection.
Upon power up or a hardware reset, the AI-7280 outputs the following characters from
the RS-232 serial port at 9600 baud.
ABL1
<CR>
GO
<CR>
They are generated by an internal boot loader program which loads the main firmware
program of the AI-7280. Following these characters, the AI-7280 is ready to accept
commands.
1.3.2 USB Port
The USB port may be used to communicate with the AI-7280 in the same manner as the
RS-232 port. The command structure and syntax is identical. However in order to use
the USB port, a suitable driver must be installed on the host PC. A Windows XP, Vista,
7 USB driver installation package is available at:
http://www.adventinstruments.com/Products/AI-7280/Downloads
Note
: The USB drivers are automatically installed if the TRsSim software has been
installed on the PC (version 3.0 and higher).
To determine if drivers are available for other operating systems, please contact technical
support.
AI-7280 Programmers Guide - Direct Control
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