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| <== Date ==> | <== Thread ==> |
|---|
| Subject: | Re: Streamdevice reads weird 1 byte null data |
| From: | Ralph Lange via Tech-talk <tech-talk at aps.anl.gov> |
| To: | EPICS Tech Talk <tech-talk at aps.anl.gov> |
| Date: | Wed, 20 Sep 2023 09:40:40 +0200 |
When not done correctly, 2-wire RS485 is prone to "echos" of the command you
send. A correctly made transceiver should disable its input while sending, but I
have had problems with newer MOXA DA-662 (but not older ones) re-enabling the
receiver too early. If MOXA uses the same chip in your nport 6650, it may be
unsuitable for 2-wire mode. You may want to try with a serial server from
another vendor.