Can I use the RS-232 interface with my computer?
Yes. The RS-232 port will most commonly be used with an external programmable control. That being said, a typical Windows computer can be utilized instead.
1. Connect the DMP8800 or DMA unit to your computer’s RS-232 port. This may require an expansion card to be installed in your computer.
2. On your PC, open the “HyperTerminal” application. Any similar ‘terminal emulator’ will suffice.
3. Enter a name or number into the “Name” field.
4. Select the appropriate COM port for your system. This is typically COM1 unless you have other COM ports in use.
5. Change the parameters for your selected COM port. We recommend setting the ‘bits per second’ value to ‘115200’. Also, change the ‘Flow control’ setting to ‘None’. Press OK to confirm.
6. Press enter in the HyperTerminal software to bring up the command prompt “DMP8800#”.
7. For this example, we’ll activate channel 1. Type “write 2 3113 1” (without the inverted commas) and press enter to activate channel 1 and turn off all other channels.
Let’s break the command down: write 2 3113 1
‘Write’ – obviously writes the command.
“2 3113 1” – The “2” denotes “DSP 2” while 3113 is the command as defined by the parameter list (ie. channel on, in this case). The final number (“1”) identifies the channel or channels affected. This is a hexadecimal value that identifies the status of the channels.
To create the appropriate hexadecimal value to activate or deactivate your channels, use a scientific calculator to change the appropriate value from binary to hexadecimal.
Explanation: The binary value will identify whether or not the channels are on (1) or off (0). For example, 0000 0001 means all channels are turned off except channel 1. 0000 0011 will activate channel 1 and 2 – all others will be off. 1010 1010 will turn on all even numbered channels. 1111 1111 means all channels are on.
Binary to Hexadecimal: Once you create the correct binary code, enter it into a binary to hexadecimal converter to get the hexadecimal value. This is the number that will go into the code you write to the device.
So, for example, if you want to turn all channels on you will need the binary number of 1111 1111 which translates to FF in hexadecimal. In this instance, you will enter “write 2 3113 FF” to activate all channels.
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