Thanks for the reply ziko
Yes I did some testing with a multimeter, and the samples seemed reasonably linear up to around +/- 4.5V, however I was only applying the voltage to channel #1 whilst monitoring all channels.
I also found that as the applied voltage approached +/- 5.0V, that the linearity started to reduce significantly on channel #1, and that the other channels would then also generate wild voltage swings of several volts, even though those channels were not connected to anything and left floating
Do you think that perhaps this oddity is due to the fact that I had left these channels floating at the time
Can I trust the samples from the other channels if they were connected to actual voltages, and if the voltage applied to channel #1 were to accidentally exceed +/- 5.0V
On a different note, I had some very pleasing results using the ADC-16 driver interface
I particularly found using the call 'adc16_get_cycle' to be of good value