User manual

COUNTER AC7E
4
Impo Electronic A/S, Svovlhatten 3, DK-5220 Odense SØ, Denmark · Tel. [phone] · Fax [phone]
Definitions:
Range: From the smallest value to the biggest that gives a correct result.
Resolution: The smallest change (difference) that can be read from the result caused by a
minimum change in input signal.
Accuracy: The extent to which the result deviates from the correct value.
COUNTER AC7E
11
Impo Electronic A/S, Svovlhatten 3, DK-5220 Odense SØ, Denmark · Tel. [phone] · Fax [phone]
1. Introduction
The IMPO AC7E Counter is the most recent version of this high-performance universal purpose
counter.
The fact that the counter is microprocessor-controlled enables counter-control to be entirely
taken over by the serial interface. This opens up the way for entirely new and very exciting
experiments, which have not previously been practicable within the framework of ordinary
teaching.
2. Connecting the AC7E
The following is a description of how to use the counter with the serial interface. Reference is
made to the general operating manual, where more detailed information is required.
2.1 Connection
A 25-pin „Cannon“ plug is located on the back of the counter. This is where to connect the
cable from the serial port RS232C/CCITT V.24 of the computer.
The computer must be configured to:
(see computer manual as to how) 1 start bit
8 data bit (ASCII)
no parity
1 stop bit
1200 baud (bit/sec.)
- if other bit rate (baud rate) is desired, the AC7E counter must be set to such.
The counter can now be switched on and will start up in fuction no. 1. The counter can then be
programmed to the desired function. The functions and operating modes of the AC7E are the same as
when manually operated using the push buttons on the front panel, except that read-out of the results
on the display is different.
3 Programming
3.1 General
The AC7E should be programmed (set) to the desired function with the appropriate commands, which
are described below.
The function LEDs will light up by way of a check for the selected function, but the actual function
selector key will not be functional. The Display Result pushbutton will be active as normal, except
where it has been programmed not to function using the command „R“.
Programming is done by sending the counter a command, such as „F4“ in the following way with
Basic (or whatever language the computer works in): PRINT#2, „F4“, if it is port#2 which is opened as
serial output port.
4. Commands
4.1 F1 Function 2: Passage time + run-time t
A
, t
B
, t
A-B
4.2 F2 Function 3: Start A - Stop B t
A-B
F Deletes read-out and prepares for new start-stop measurement.