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Press the SYSTEM menu button
(F3 soft key)
direction key to move the cursor to the port
format
RS232C soft key.
Serial port main parameters
Transfer Method
Full-duplex asynchronous communication with start and stop bits
Baud Rate
9600 bps/19200bps/38400bps/115200bps
Data Bit
8 BIT or 7 BIT
Stop Bit
1 BIT or 2 BIT
Parity Check
No Parity/Odd Parity/Even Parity
Terminator
NL (line break, ASCII code 10)
Handshake Method
Software handshake
Connector
DB9 Core
Software Protocol
Since the hardware handshake communication control is not used on the RS232 interface, in order
to reduce the possibility of data loss or data error in the communication, the tester uses the character
echo method for software communication. Please refer to the following when programming
computer communication software:
1)
The command string syntax and format are described in Chapter 5.2 “Serial Port Commands
Instruction ”
2)
The command sent by the host is transmitted in ASCII code, the NL (ie, newline character,
ASCII code 10) is used as the terminator, the tester starts executing the command string after
receiving the terminator.
3)
The instrument will send the character back to the host immediately after receiving one
character. The host should continue to send the next character after receiving the return
character. If you do not receive the returned characters, there may be several reasons:
1.
Serial port connection failure. Make sure TXD is connected to the other side’s RXD.
2.
Check that the RS232 port function is enabled.
3.
The tester is executing a bus command and is temporarily unable to respond to serial
acceptance.
At this point, the last sent character is ignored by the tester, if you want to
ensure the integrity of the command string, the host should resend the unreturned
characters.
4)
The tester sends information to the host only in the following two cases:
1.
The command character of the host is received normally and the character is looped back.
2.
Executing the query command to send the query result to the host.
5)
Once the tester executes the query command, the query result will be sent immediately,
regardless of whether the current command string has been completely executed.
Therefore,
there can be multiple queries in a command string, but the host must have a corresponding
number of read results. This protocol recommends that only one query be included in a single
command string.
6)
The result of the query is sent in ASCII code string, with NL (ie. newline, ASCII code 10) as
the terminator.
7)
When the tester sends the query result, it is sent continuously (character interval is about 1ms),
and the host should be in the state of accepting data, otherwise, data loss may occur.
8)
Once the host generates the query, please ensure that all query results are read (once NL is
received, meaning end) to avoid the conflict between the query and the loopback; similarly, the
