Hi,
I have a control box which works stand alone or with additional box connected.
In standalone mode when the unit is switched on H is displayed in the screen.
If additional box is connected and unit is switched on X is shown in the screen. My problem is the unit does not see the box when connected and as a result shows H all the time. I have what looks like a RS232 cable that connects the unit to the box. What test can I do to see if the signal question is being sent from unit to box then signal answer from box to the unit. Failing that I will be looking for advice where the circuit board could be checked out.
Many thanks from a newbie.
I have a control box which works stand alone or with additional box connected.
In standalone mode when the unit is switched on H is displayed in the screen.
If additional box is connected and unit is switched on X is shown in the screen. My problem is the unit does not see the box when connected and as a result shows H all the time. I have what looks like a RS232 cable that connects the unit to the box. What test can I do to see if the signal question is being sent from unit to box then signal answer from box to the unit. Failing that I will be looking for advice where the circuit board could be checked out.
Many thanks from a newbie.
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