Messages in this thread | | | Date | Thu, 8 Feb 2024 16:46:18 +0100 | Subject | Re: [PATCH v5 2/6] serial: 8250: Support separate rs485 rx-enable GPIO | From | Farouk Bouabid <> |
| |
Hi Christoph,
On 30.01.24 13:29, Christoph Niedermaier wrote: > [Einige Personen, die diese Nachricht erhalten haben, erhalten häufig keine E-Mails von cniedermaier@dh-electronics.com. Weitere Informationen, warum dies wichtig ist, finden Sie unter https://aka.ms/LearnAboutSenderIdentification ] > > From: Farouk Bouabid > Sent: Monday, January 29, 2024 9:57 AM > > Hi, > >> On 26.01.24 20:58, Lino Sanfilippo wrote: >>> [Some people who received this message don't often get email from linosanfilippo@gmx.de. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] >>> >>> Hi, >>> >>> On 26.01.24 18:27, Farouk Bouabid wrote: >>>> From: Heiko Stuebner <heiko.stuebner@cherry.de> >>>> >>>> The RE signal is used to control the duplex mode of transmissions, >>>> aka receiving data while sending in full duplex mode, while stopping >>>> receiving data in half-duplex mode. >>>> >>>> On a number of boards the !RE signal is tied to ground so reception >>>> is always enabled except if the UART allows disabling the receiver. >>>> This can be taken advantage of to implement half-duplex mode - like >>>> done on 8250_bcm2835aux. >>>> >>>> Another solution is to tie !RE to RTS always forcing half-duplex mode. >>>> >>>> And finally there is the option to control the RE signal separately, >>>> like done here by introducing a new rs485-specific gpio that can be >>>> set depending on the RX_DURING_TX setting in the common em485 callbacks. >>>> >>> we just added the rx_during_tx_gpio to the serial core. >>> Why cant you use this GPIO for your purpose? >>> >>> Regards, >>> Lino. >> What we are trying to implement is a gpio that emulates the RTS signal >> itself as we do not have a dedicated RTS signal that can be controlled >> through MCR. The rx during tx state in our case is a fixed state of >> "NO_RX_WHILE_TX" > Why can't the property rts-gpios be used here for this purpose?
Yes that indeed serves our purpose. Thank you for the suggestion.
Regards
Farouk
> > > Regards > Christoph
| |