- From: M. Koehrer <mathias_koehrer_at_arcor.de>
- Date: Thu, 5 Oct 2006 08:39:07 +0200 (CEST)
Hi everybody, I am trying to get the NI 6259 (M series) board running with comedi (0.7.73 and also CVS snapshot). When reading from the analog input a strange effect appears: Whenever the input voltage is negative, the value of data in comedi_data_read() is fine, it is something between 0x00000000 and 0x00007fff. However, whenever the input voltage is positive, the higher two bytes of data become 0xffff, the values are 0xffff8000 (for 0V) up to 0xffffffff (5V which is the maximum here). It looks as if the higher two bytes get set to 0xffff whenever the voltage becomes positive. When I do an AND (&) operation on the value with 0x0000ffff (which is the maximum sample of this channel, obtained by comedi_get_maxdata()) everything is fine. The values have than the range from 0 (for -5V) to 0xffff (for +5V). Any idea on that?!? Can this AND-operation performed as default to fix this issue? Does it work with all boards? Thanks for any feedback on this strange issue. Regards Mathias -- Mathias Koehrer mathias_koehrer_at_arcor.de Viel oder wenig? Schnell oder langsam? Unbegrenzt surfen + telefonieren ohne Zeit- und Volumenbegrenzung? DAS TOP ANGEBOT JETZT bei Arcor: günstig und schnell mit DSL - das All-Inclusive-Paket für clevere Doppel-Sparer, nur 44,85 € inkl. DSL- und ISDN-Grundgebühr! http://www.arcor.de/rd/emf-dsl-2
Received on 2006-10-05Z05:39:07