Is it possible to display a waveform with fixed length and fixed starting point?

Hi,
I am using DAQ assitant to acquire voltage and current measurment of my device. The voltage is a pure sine wave and current is a periodic waveform with phase difference and distortion. I use waveform chart to display the waveform of voltage and current waveform in seperate charts and they work fine.But the waveforms look like moving to the right all the time, in another way ,the phase is always shifting. Now i want to display the waveforms of both with fixed length (say 2 cycle) and also in a same chart. Apart from that, i also want to display the voltage waveform starting form 0 degree (a fixed point )rather than moving all the time. In this case, i can observe the angle difference between voltage and current. Is there any method to achieve this purpose?
Many Thanks,
Hao

Hao,
first of all, you are using a chart which has three options for updates if the chart is "full":
Strip chart (default)
Scope chart
Sweep chart
These are called "update mode". Test the modes yourself.
Also you have to know that you will not likely have an integer number of periods of your signal in the display of the chart. Therefore, a continuous signal will "move" the graph from update to update.
You can implement some algorithm to discard data to maintain a static "trigger" level for display, but as stated, it will leave gaps in the signal. These gaps are not a concern unless you use the displayed signal for analysis (e.g. FFT).
Norbert
CEO: What exactly is stopping us from doing this?
Expert: Geometry
Marketing Manager: Just ignore it.

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Hi,
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PROBLEM
Apple will not replace, as promised, the iPhone 5 (A1429 GSM model) that they gave me in London, UK, with an iPhone 5 (A1429 CDMA model).
BACKGROUND
My iPhone 5 (A1429 CDMA model) was purchased this year in September on an existing Verizon Wireless (VZW) line using an upgrade. The purchase took place in California and the product was picked up using Apple Personal Pickup through the Cerritos Apple Retail Store. I will refer to this phone at my "original" phone.
The original phone was taken into the Apple Store Regent Street in London, England, UK on November 15, 2012. The reason for this visit was that my original phone's camera would not focus.
The Apple Store Regent Street verified there was a hardware problem but was unable to replace the part.
The Apple Store Regent Street had me call the US AppleCare. At first they denied support, but then a supervisor, name can be provided upon request, approved the replacement of my original phone with an iPhone 5 (A1429 GSM model) as a temporary solution until I got back in the US. And approved that the GSM model would be replaced with a CDMA model when I came back to the US. I will refer to the GSM model as the "replacement". They gave me the case number --------.
The Apple Store Regent Street gave me the replacement and took the original. The first replacement did not work for reasons I do not understand. They switched out the replacement several times until they got one that worked on the T-Mobile nano SIM card that I had purchased in England, UK. Please refer to the repair IDs below to track the progression of phones given to me at the Apple Store Regent Street:
Repair ID ----------- (Nov 15)
Repair ID ----------- (Nov 16)
Repair ID ----------- (Nov 16)
The following case number was either created in the UK or France between November 15 to November 24. Case number -----------
On November 19, 2012, I went to France and purchased an Orange nano SIM card. The phone would not activate like the first two repair IDs above.
On November 24, 2012, I went to the Apple Store Les Quatre Temps. The Genius told me that my CDMA phone should not have been replaced with a GSM model in the UK and that this was clearly Apple's fault. They had me call the AppleCare UK.
My issue was escalated to a tier 2 UK AppleCare agent. His contact information can be provided upon request. He gave me the case number -----------.
The UK tier 2 agent became upset when he heard that I was calling from France and that the France Apple Store or France AppleCare were not helping me. He told me that my CDMA phone should not have been replaced with a GSM model in the UK and that this was clearly Apple's fault.
The UK tier 2 agent said he was working with engineers to resolve my problem and would call me back the next day on November 25, 2012.
While at the Apple Store Les Quatre Temps, a Genius switched the phone given to from repair ID ----------- with a new one that worked with the French nano SIM card.
Also, while at the Apple Store Les Quatre Temps, I initiated a call with AppleCare US to get assistance because it seems that AppleCare UK was more upset that France was not addressing the issue rather than helping me. I have email correspondance with the AppleCare US representative.
A Genius at the Apple Store Les Quatre Temps switched the replacement with a new GSM model that worked on the French SIM card but would not work if restored, received a software update, or had the SIM card changed. This is the same temporary solution I received from the Apple Store Regent Street in the UK.
By this point, I had spent between 12-14 hours in Apple Store or on the phone with an AppleCare representative.
Upon arriving in the US, I went to my local Apple Store Brea Mall to have the replacement switched with a CDMA model. They could not support me. He told me that my CDMA phone should not have been replaced with a GSM model in the UK and that this was clearly Apple's fault. My instructions were to call AppleCare US again.
My call with AppleCare US was escalated to a Senior Advisor, name can be provided upon request, and they gave me the case number -----------. After being on the phone with him for over an hour, his instructions were to call the Apple Store Regent Street and tell them to review my latest notes. They were to process a refund for a full retail priced iPhone 5 64BG black onto my credit card so that I could use that money to buy a new iPhone 5 64GB black at the Apple Store Brea Mall to reoslve the problem.
The Apple Store Regent Street did not process my refund. He, name can be provided upon request, told me that the AppleCare US did not do a good job reviewing my case, that they were incapable of getting to the bottom of it like they were, and instructed me to call AppleCare US and tell them to review this case number and this repair id. I asked if he read the notes from the AppleCare US Senior Advisor and he would not confirm nor deny. When I offered to give him the case number he accepted but it seemed like would do no good. Our call was disconnected. When I tried calling back the stores automated system was turned on and I could not get back through.
Now I have the full retail price of an iPhone 5 64GB black CDMA on my credit card and Apple will not process the refund as they said they would.
I've, at this point, spent between 14-16 hours at Apple Stores or on the phone with AppleCare representatives, and still do not have the problem resolved.
SOLUTION
AppleCare US and AppleCare Europe need to resolve their internal family issues without further impacting their customers.
Apple is to process a refund to my credit card for the cost of a full retail priced iPhone 5 64GB black.
DESIRED OUTCOMES
I have an iPhone 5 (A1429 CDMA model) that works in the US on VZW as it did before I received the replacement phone in the UK.
Apple covers the cost of the solution because I did not create the problem.
Apple resolves their internal issue without costing me more time, energy, or money.
This becomes a case study for AppleCare so that future customers are not impacted like I have been by their support system.
Does anyone have recommendations for me?
Thank you!
<Edited by Host>

Thanks, but I've been on the phone with AppleCare US (where I am and live) and AppleCare UK. They continue bouncing me back and forth without helping resolve the problem.
Perhaps someones knows how to further escalate the issue at Apple?

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Hi Guys,
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http://www.cisco.com/en/US/tech/tk722/tk809/technologies_configuration_example09186a008076317c.shtml#switch
I go through some references:
3.5 RADIUS-Based VLAN Access Control
As discussed earlier, each SSID is mapped to a default VLAN-ID on the wired side. The IT administrator may wish to impose back end (such as RADIUS)-based VLAN access control using 802.1X or MAC address authentication mechanisms. For example, if the WLAN is set up such that all VLANs use 802.1X and similar encryption mechanisms for WLAN user access, then a user can "hop" from one VLAN to another by simply changing the SSID and successfully authenticating to the access point (using 802.1X). This may not be preferred if the WLAN user is confined to a particular VLAN.
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extract from: Wireless Virtual LAN Deployment Guide
http://www.cisco.com/en/US/products/hw/wireless/ps430/prod_technical_reference09186a00801444a1.html
==============================================================
Dynamic VLAN Assignment with RADIUS Server and Wireless LAN Controller Configuration Example
http://www.cisco.com/en/US/tech/tk722/tk809/technologies_configuration_example09186a008076317c.shtml#switch
==============================================================
Controller: Wireless Domain Services Configuration
http://www.cisco.com/en/US/products/hw/wireless/ps4570/products_configuration_example09186a00801c951f.shtml
Any help on this issue is appreicated.
Thanks.

I'm not sure if the Autonomous APs have the option for AAA Override. On the WLC, I can go into the BSSID, Security, Advanced, and there's a checkbox that I would check to allow a Radius server to send back the VLAN.
I did a little research and it looks like the 1300 may give this option but instead is defined as "VLAN Override". I've found the release notes for 12.3(7)JA5 (not sure what version you're running) that give mention and a link to configuring EAP on page 4: http://www.ciscosystems.ch/en/US/docs/wireless/access_point/1300/release/notes/o37ja5rn.pdf
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Is it possible to display a waveform with fixed length and fixed starting point?

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