Hardware RS485 support on the SAMD51 = Actually not there?

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Ada485
 
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Hardware RS485 support on the SAMD51 = Actually not there?

Post by Ada485 »

Per 34.6.3.6 - RS485 (pg 863 of the D51 reference manual - DS60001507A):

The D51 only includes support for automatic TE (transmit enable) pin control with optional programmable guard time to control an external line driver in half-duplex mode. It does not have a differential line driver or differential line receiver required for RS-485 integrated on the chip.

But Adafruit advertises it as supporting RS485? Except when we went to actually use it, it turns out there is no software support and what appears to be almost no actual hardware support either.

Which is actually kind of sad considering how simple the protocol is and how long it has been in use. We can still use a companion chip to get it to do what we want but that is exactly what we were trying to avoid doing.

Adafruit, are we understanding this correctly?

We only need half duplex RS485 support, which presumably even the D21 in the Adafruit Zero offers?

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Re: Hardware RS485 support on the SAMD51 = Actually not ther

Post by adafruit2 »

hiya - nothing has changed since we last replied...if you want RS485, you have to add it yourself as we don't, we do not have software support for it and there is no plans to do so at this time!

please keep this topic to your thread viewtopic.php?f=8&t=142073

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