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5.2.3 Selecting Baud Rate
The baud rate is the rate at which Model TH1942 multimeter and the computer communicate. Choose
one of these available rates:
38.4k
19.2k
9600
4800
2400
1200
600
Note:
Factory default baud rate is 9600.
Before you choose a baud rate, make sure the programming terminal that you are connecting to the
TH1942 can support the baud rate you selected. Both the multimeter and the other device must be
configured for the same baud rate.
Perform the following steps to select a baud rate:
1. Press
Shift
→
to enter the menu on the menu level,
―
A: MATH MEU
‖
will be displayed.
2. Use
or
key to move across to the SYS MEU on the menu level,
―
C: SYS MEU
‖
will be
displayed.
3. Press
to move down to the command level within the SYS MEU,
―
1: BEEP STR
‖
will be
displayed.
4. Use
or
key to move across to the BAUD RATE command,
―
2: BAUD RATE
‖
will be
displayed.
5. Press
to move down a level to set the baud rate.
6. Use
or
key to select a baud rate.
7. Press
(ENTER) to confirm the selection. The message
―
SAVED
‖
will be displayed to show
that the change is now in effect. TH1942 will exit the parameter level and move up a level to the
command level.
8. Press
Shift
→
key to exit from the menu and return to the measurement status.
5.2.4 Software Protocol
Since the hardware handshaking lines CTS and RTS are not used by TH1942, the multimeter uses the
character return method to decrease the data losses and errors during communication. Please refer to
the content below before programming communication software.
1. For command syntax and format, refer to Chapter 6 Command Reference.
2. The controller transmits the command using the ASCII code with <LF> or <CR> as the terminal
character. TH1942 executes the command after the terminal character is received.
3. The character received by TH1942 will be sent back to the controller again. The controller will not
send the next character until the last returned character is received correctly from TH1942. If the
controller fails to receive the character sent back from TH1942, the possible reasons are listed as
follows:
