On Wed, 2 Mar 2016, Oliver Neukum wrote:
On Tue, 2016-03-01 at 09:54 -0800, amarburg@xxxxxxxxxxxxxxxxxx wrote:
From: Aaron Marburg <amarburg@xxxxxxxxxxxxxxxxxx>
The USOPTL4-4P and USOPTL4-2P USB-to-quad/dual RS-485/422 hubs use the
Moschip 7840/7820. For correct operation in RS-485, the chip must be
configured in “RS-485 mode” through the scratchpad register as per the
datasheet. This strobes the DTR line on transmission, enabling the driver
on the RS485 transceiver chip.
I think if you include a config option to do this, you should
also enable the canonical way of using an ioctl(). That means
you need to support rs485_config().
Regards
Oliver
Thank you for that pointer, I was not familiar with that IOCTL. I will
see what's required for implementation.
Thanks,
Aaron
