- From: Stienen, A.H.A. (CTW) <"Stienen,>
- Date: Wed, 11 Jan 2006 17:43:42 +0100
Hello,
I've build a Simulink S-Function block for encoder devices, based on the
NI_660x and RTAI-Lab AI driver and as an addition to the AI, AO, DI and
DO devices blocks already available for RTAI-Lab. I'm wondering whether
this block can be useful for other quadrature encoder devices in RTAI-Lab.
Most of the code in the S-Function is pretty Comedi basic
(comedi_data_read, etc), I think, but I'm not sure whether the
configuration process of the NI_660x is similar to other quadrature
encoders.
The configuration code I'm currently using is based on the NI_660x test
example of Klaas Gadeyne. It comes down to:
comedi_insn insn;
lsampl_t config_data[4];
insn.insn = INSN_CONFIG;
insn.n = 1; // Is relevant to config! :)
config_data[0] = INSN_CONFIG_GPCT_QUADRATURE_ENCODER;
config_data[1] = quadraturemode; // {GPCT_X1, GPCT_X2, or GPCT_X4}
config_data[2] = indexphase; // {GPCT_IndexPhaseHighHigh,LH,LL,HL}
config_data[3] = indexreset; // {0,GPCT_RESET_COUNTER_ON_INDEX}
insn.data = config_data;
insn.subdev = subdev;
insn.chanspec = CR_PACK(channel,0,0);
comedi_do_insn(dev,&(insn));
Where 'dev' points to a /dev/comediX, 'subdev' is the result of a
comedi_find_subdevice_by_type(dev,COMEDI_SUBD_COUNTER,0), and 'dev'
'quadraturemode', 'indexphase', 'indexreset' and 'channel' are given by
the user via the Simulink S-Function mask. After configuration, I can
read the encoder signal with a comedi_data_read.
Is this configuration process usable for other encoders too? I only have
the NI_660x card. Does anybody know of other quadrature encoders
supported by Comedi?
Kind regards,
Arno Stienen.
--
____
/ |_| <<< IR. ARNO H.A. STIENEN >>>
|_ O | Biomechanical Engineering | http://www.bw.ctw.utwente.nl
|_|__/ a.h.a.stienen_at_utwente.nl | +31-(0)53-489-4778
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Received on 2006-01-11Z16:43:42