The OM API does not supply a call to change the scan rate on the list. It does provide a mechanism to add and delete individual points to a list. (The CP's use this for peer-to-peer to minimize list usage.) The FoxAPI designers were given the task of consolidating all FoxAPI user's needs so that a given point could be used by multiple programs and yet appear to the CP as having a single user. Previously, a single point would be sent from the same CP to the same AW once for each user of the point. In large installations, this was a problem. The designers of FoxAPI given the goals and the constraints decide to fix the scan rate and add points the list. Other designs are possible, e.g., a high speed list and a slow speed list and points are put on one or the other depending on the rsr in the scopen call, but that is kind of irrelevant at this point. Regards, Alex Johnson Invensys 10707 Haddington Houston, TX 77063 713.722.2859 (office) 713.722.2700 (switchboard) 713.932.0222 (fax) ajohnson@xxxxxxxxxxx <mailto:ajohnson@xxxxxxxxxxx> For the latest information on ArchestrA, go to www.invensys.com/Archestra.html <http://www.invensys.com/divisions/Archestra.html> . -----Original Message----- From: stan [SMTP:stanb@xxxxxxxx] Sent: Thursday, December 12, 2002 7:16 AM To: foxboro@xxxxxxxxxxxxx Subject: Re: [foxboro] FOXAPI Configuration for Foxhistory Ver 2.0 On Wed, Dec 11, 2002 at 04:24:18PM -0500, Johnson, Alex (Foxboro) wrote: > > As I said, fastest_rsr sets the scan rate for all points opened by FoxAPI - > IP.21 uses FoxAPI. > > > The original AIS API allowed each data set to be opened with a different > scan rate. FoxAPI maintains the same call, but ignores the read scan rate > specification. The OM lists that implement the data set are all opened with > fastest_rsr. > I don't mean to sound critical here, but this apears to be a less desirbale way to work than the original AIS desing. Could you clarify what the _advantage_ of not having indivisual scan rates for each data consumer are? -- "They that would give up essential liberty for temporary safety deserve neither liberty nor safety." -- Benjamin Franklin _______________________________________________________________________ This mailing list is neither sponsored nor endorsed by Invensys Process Systems (formerly The Foxboro Company). Use the info you obtain here at your own risks. Read http://www.thecassandraproject.org/disclaimer.html foxboro mailing list: http://www.freelists.org/list/foxboro to subscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=join to unsubscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=leave _______________________________________________________________________ This mailing list is neither sponsored nor endorsed by Invensys Process Systems (formerly The Foxboro Company). Use the info you obtain here at your own risks. Read http://www.thecassandraproject.org/disclaimer.html foxboro mailing list: http://www.freelists.org/list/foxboro to subscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=join to unsubscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=leave