Do I need RTS CTS to test if a serial device is ready?

I have a Feather Huzzah successfully sending data to a Zebra printer via a TTL-RS232 converter (NS-RS232 Nulsom). Lines 3V, GND, RX, and TX are connected. But I want to query the printer to see if it is on / connected. I'm not receving any on RX when I send a command that should provide a response. Would implementing RTS / CTS be the right direction to pursue? Thanks, Tim

Depends entirely upon whether the Zebra printer implements RTC/CTS or DTR (which might be more useful).

Pete

P.S. Sending a command which must provide a response is just as useful. If there no response to a command within, say, 100ms you can assume that the printer isn't there for one reason or another. Then you won't need to mess about with extra wiring.

Pete

No implementation necessary. Just jumper the pins on the printer.

Paul

To clarify, I am able to send print commands and the printer prints bar codes, text, whatever. But if I send a Configuration Inquiry (UQ), for example, which is supposed to generate a response, I don’t get one.

The printer model is GK420d. I will try jumping the CTS and RTS pins on the RS232 converter (hopefully won’t blow anything up).

Perhaps the manual explains how the printer is supposed to respond to queries. The zebra website won't download the manual so I can't help.

Pete

tlawless:
To clarify, I am able to send print commands and the printer prints bar codes, text, whatever. But if I send a Configuration Inquiry (UQ), for example, which is supposed to generate a response, I don’t get one.

The printer model is GK420d. I will try jumping the CTS and RTS pins on the RS232 converter (hopefully won’t blow anything up).

RS-232 is designed to withstand forever sorting of any pins to any other, in any combination. Also designed to withstand up to 25 volts on any pin forever. Most devices never got beyond about 12 volts.

Bottom line is there nothing you can do within the RS-232 spec to harm you devices.

Paul