On 09.06.2022 10:52:03, Dario Binacchi wrote:
> > > The help option of slcan_attach and slcand prints " -f (read status
> > > flags with 'F\\r' to reset error states)\n" I looked at the sources of
> > > the adapter I am using (USBtin, which uses the mcp2515 controller).
> > > The 'F' command reads the EFLG register (0x2d) without resetting the
> > > RX0OVR and RX1OVR overrun bits.
> >
> > The Lawicel doc [1] says 'F' is to read the status flags not to clear
> > it. However commit 7ef581fec029 ("slcan_attach: added '-f' commandline
> > option to read status flags") [2] suggests that there are some adapters
> > that the reading of the status flag clears the errors. IMHO the 'F'
> > command should be send unconditionally during open.
> 
> When in doubt I would follow the slcand / slcan_attach approach, that don't
> send the 'F \ r' command by default. We would be more backward compatible
> as regards the sequence of commands to be sent to the controller.

Ok, keep it this way.

Marc

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