Search found 7 matches

by Enrico Segre
Tue Jun 08, 2004 2:42 pm
Forum: BioSemi Software (ActiView executable)
Topic: precise timing of the read in lag
Replies: 2
Views: 7140

hmmm, interrupt latencies. This explains it. The filling of the receiver FIFO is deterministic, the lag between last processed and most recent data in the ringbuffer also (it is variable, but directly dependent on the pointers), but the link between the two depends on an interrupt and breaks the det...
by Enrico Segre
Mon Jun 07, 2004 2:41 pm
Forum: BioSemi Software (ActiView executable)
Topic: precise timing of the read in lag
Replies: 2
Views: 7140

precise timing of the read in lag

Hi, I still have one question connected with my previous posts. For the application I have in mind, I need to analyse online some data, and to provide trigger output depending on the result. It is not paramont that the online analysis is fast, but it is that the timing is known. The principle of the...
by Enrico Segre
Thu Jun 03, 2004 1:30 pm
Forum: BioSemi Software (ActiView executable)
Topic: Timing accuracy of USB trigger out
Replies: 8
Views: 16772

Thanks once more for your reply. Such times are indeed acceptable for my present application. I do agree that as a monitoring/recording interface, Actiview is perfect as it is, and there is no need to enforce such strict timing, provided (as it is) that there is no data loss. The problem arises only...
by Enrico Segre
Wed Jun 02, 2004 4:06 pm
Forum: BioSemi Software (ActiView executable)
Topic: Timing accuracy of USB trigger out
Replies: 8
Views: 16772

Thanks for the answer, Coen! Just a few comments: >Actually, the problem is not in the trigger output thread, but rather in >the (variable) time needed to do the online data analysis which should >generate the trigger. The incoming EEG data is stored into a large >ringbuffer. ActiView constantly pro...
by Enrico Segre
Wed Jun 02, 2004 11:12 am
Forum: BioSemi Software (ActiView executable)
Topic: Timing accuracy of USB trigger out
Replies: 8
Views: 16772

Timing accuracy of USB trigger out

I'm programming some custom modification to ActiView 5.19. The goal, as said in my other posts, is to add some online analysis, whose results generate trigger output. The aim is to reach very precise timings, with latency times, possibly, within 1ms (1ms is the limit achievable by using Labview time...
by Enrico Segre
Mon May 31, 2004 3:06 pm
Forum: BioSemi Software (ActiView executable)
Topic: Bug? ActiView 5.19, trig-in does "pause save"
Replies: 1
Views: 6835

Bug? ActiView 5.19, trig-in does "pause save"

I'm observing something strange in my setup, both in ActiView 5.19 low res and in my further elaborations thereof -- if all the trigger inputs are disconnected (i.e. pulled up as on) except for in1, then any time in1 goes up the button "Pause Save" becomes active. Is this a known bug? My solution so...
by Enrico Segre
Mon May 31, 2004 2:31 pm
Forum: BioSemi Hardware
Topic: Best way to connect a generator to the active electrodes
Replies: 2
Views: 9805

Best way to connect a generator to the active electrodes

I am implementing some custom modifications to Actiview, in order to make it capable to perform some online analysis and triggering. As a part of the developement and testing, I need to connect a small signal generator to some electrodes of the Active Two. My question is, which is the advisable way ...