-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 9/19/2012 1:37 PM, Roland Jollivet wrote: > Hi All > > Can anyone tell me; > > Considering the near obsoletion of the parallel port, and the > latency of USB, is it not possible to do CNC control using the > SMBus as part of the PCI bus?
Not really. I've got an I2C bus (same as SMBus) currently running off the parallel port to give me some analog inputs for my 3D printer. Assuming you can run at 100 KHz, that rate is a serial bit rate, *NOT* a transaction rate. That means a typical writes (which typically take 27 bit times) happen at a rate of about 3700 *BYTES* per second, and reads are even slower (typically 36 or more bit times). Conventional serial ports are _much_ faster and even those are typically not fast enough for closed-loop motion. The bus works for me because I'm measuring temperature via an ADC, and the thermal constants are really slow, so a few readings per second is fine. - -- Charles Steinkuehler [email protected] -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAlBaHnIACgkQLywbqEHdNFyLDQCeM5Qf/Kz2Z3HhVWN1aAFREt7N i2MAnRq42mrDFZKQvnFDJmve1g7sa6af =n8l+ -----END PGP SIGNATURE----- ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
