AI Ranges

• From: Richard Bytheway <Richard.Bytheway_at_bede.co.uk>
• Date: Fri, 15 Nov 2002 11:48:09 -0000

I am trying to get my PCIM-DAS1602 driver to support software selection of ranges, however, I cannot make sense of how the range selection mechanism is supposed to work.

I have tried to copy the cb_pcidas driver, since this is a similar card.

I have a pointer to a comedi_lrange in my device details:

	typedef struct cb_pcimdas_board_struct
	{
		<snip>
		comedi_lrange *ranges;
	} cb_pcimdas_board;

and set this to a pointer to an array of ranges:

	static comedi_lrange cb_pcimdas_ranges =
	{ 8,
		{	BIP_RANGE(10),
			BIP_RANGE(5),
			BIP_RANGE(2.5),
			BIP_RANGE(1.25),
			UNI_RANGE(10),
			UNI_RANGE(5),
			UNI_RANGE(2.5),
			UNI_RANGE(1.25)
		}
	};

static cb_pcimdas_board cb_pcimdas_boards[] =
{
	{
		<snip>
		ranges:		&cb_pcimdas_ranges,
	},
};


As far as I can see, this is all that is done in the cb_pcidas driver.

I use comedilib/demo/inp.c to test:
	$ ./inp -s0 -c0
	16811
	$ ./inp -s0 -c0 -r0
	16810
	$ ./inp -s0 -c0 -r1
	bad chanlist[0]=0x00010000 n_chan=16 range length=1
	/dev/comedi0: Success
	$

I don't understand this error message. Yes, there are only 16 channels, but I am asking for channel 0, which works without -r1.

What am I missing? 


Richard Bytheway

Received on 2002-11-15Z11:48:09