On Sun, 17 May 2026 15:58:43 +0100 Jonathan Cameron <[email protected]> wrote:
> On Fri, 08 May 2026 18:00:25 +0100 > Rodrigo Alencar via B4 Relay <[email protected]> > wrote: > > > From: Rodrigo Alencar <[email protected]> > > > > Add custom ABI documentation file for the DDS AD9910 with sysfs entries to > > control Parallel Port, Digital Ramp Generator and OSK parameters. > > > > Signed-off-by: Rodrigo Alencar <[email protected]> > I'm fine with phase and frequency as defined, but for the scaling it made me > wonder. > For outvoltage0 channels the assumption the value is the peak voltage so if > we know what input to be modulated by the ramp generator can we express them > in volts (well milivolts) rather than as a scaling multiplier? > > That seems to me like it fits better with the overall ABI. > > > +What: > > /sys/bus/iio/devices/iio:deviceX/out_altvoltageY_scale_offset > > +KernelVersion: > > +Contact: [email protected] > > +Description: > > + For a channel that allows amplitude control through buffers, > > this > > + represents the value for a base amplitude scale. The actual > > output > > + amplitude scale is a result with the sum of this value. > > + > > > + > > +What: > > /sys/bus/iio/devices/iio:deviceX/out_altvoltageY_scale_roc > > Silly question perhaps but can work out how this related to millivolts/sec > That might make a more intuitive interface than scaling multiplier per sec > Perhaps the combination with offset makes this impossible though maybe that > could be a expressed as a voltage offset? Afterall if the amplitude being > scaled is 5V then 5 * (offset + scale) = 5 * offset + 5 * scale > See thread on next patch. I think I argued myself out of this. > > +KernelVersion: > > +Contact: [email protected] > > +Description: > > + Amplitude scale rate of change in 1/s for channels that ramp > > + amplitude. This value may be influenced by the channel's > > + sampling_frequency setting. > > >
