Test and Measurement Forum

I downloaded document psw044.pdf (Picoscope User manual) several weeks ago and on
the basis of the features described chose the ADC-212/3 module for evaluation. The
software that came on both copies of the CD-ROM was not the latest version and the
features available were not as descibed in the User Manual. I downloaded the latest release
versions for Windows XP and Windows 98 for use on two laptop PCs.

For the main application that I intend to apply Picsoscope the ADC-212/3 has a fast enough
sampling rate to allow me to capture repetative waveforms with sufficient number of samples
for capturing for subsequent post-processing with another application.

One minor irritation with the Picoscope software is the message indicating that I need some
other Help file when I seek Help from the Scope Advanced Options window (page 52 in User
Manual). "(Topic does not exist. Contact your application vendor for an updated Help file
(129))"

Q1. How do I get the right Help file to enable the correct response from within the Picoscope
software?

Another application for which I considered the ADC-212/3 requires a typical timebase setting
of 5 microSec/division. I guessed (rightly) that the maximum sampling rate of 3 MS/sec
would give problems of 'jitter' on triggering, especially if I were to use both A and B channels,
as the smallest sampling time is 0.66 microSec. I had read somewhere that the ADC-212/3
does not have the ETS (Equivalent Time Sampling) feature that would (or maybe) allow me
to reduce the 'jitter'. The latest version of the Picoscope software gives a contrary
impression in that the ETS feature in the Trigger window (page 29 in User Manual) is NOT
greyed out and can be checked (but when the same window is displayed again, the check
box is empty). In addition, the Scope Advanced Options indicate ETS is enabled and
accepts changes to the ETS oversample (2..5).

Q2. Please confirm that ETS is not (yet) allowed for the ADC-212/3 - or is it supposed to be?
If not, is there any reason you could not get the ADC-212/3 working with ETS?

I am considering producing an aplication, using Delphi 3, to run the ADC 212/3 (and perhaps
alternative, similar modules in the ADC2xx range, that use ETS.

Q3. Where can I find the information that describes the ETS function calls? (It is not in the
ADC 2xx manual v1.1, but the function headers for ETS are to be found in the adc200.inc
file that is referred to in the Delphi project file example.)

My experience with Delphi does not cover calls to DLLs. Please clarify the following: -

Q4. In adc200.inc the function header for adc200_get_values uses untyped variables for the
two buffer parameters, buffer_a and buffer_b, but there are no corresponding variables
declared in the adc200.dpr or elsewhere. Is this correct? (Ignore this one! I've spotted the
declarations of buffer_a and buffer_b in adc200.pas.)

One final comment relates to the implementation of the 'Both channels, alternate' setting in
the Channels window (page 35 of User Manual). I have a special piece of test equipment
that feeds a repetative signal from two sources, alternately to the same channel. When the
EUT (Equipment Under Test!) is OK, the alternate signals are identical. When it is not OK,
the alternate signals differ. Using the persistence feature of Picoscope the difference can be
seen on one channel. However, using the "current (unfiltered)" setting and the SAME signal
fed to BOTH channels, the alternate signal swops between the red to blue traces from time to
time.

Q5 What is the explanation for this?

Hi,

Tnak you for your post.

I have looked into you post and found that the help button in Settings | options | Advanced has not been configured. There is no update of the help manual.

I have tried to repeat your ETS problem. I am using 5.10.5, with a ADC-212/3 connected I open Settings | Trigger and the ETS check box is always greyed out (disabled). Please can you inform me what version you are using and the bactch number of the unit. The batch nuber can be retrieved from Help | About. It should also have the calibration date.

ETS is not available for the ADC-212/3 only for ADC-212/50 and ADC-212/100. It is not likely to be introduced for the ADC-212/3.

I have looked at the .pdf file for ADC-212 and agree that the ETS functions are missing, I have passed these comments onto our technical author. These are available in the electronic help manual for the ADC-212, and can be downloaded from here. Download the ADC-212 self extracting zip file for Examples, drivers and manuals.

Unfortunately, your fifth question has confused me. Could you please send me some .psd files showing the display and an explanation of your expected results and when you get inconsistences.

tech@picotech.com

Best regards,

Mark,

Many thanks for your speedy response to my questions.

Re my Q2:
The version of Picoscope software that I have downloaded is the latest RELEASE version
(as mentioned in my preamble to Q1). This is version 5.09.4 - 32 bit - as on Picotech website
now. The version you mention (5.10.5) is the BETA version currently available from the
website. I did not not download the BETA versions as my understanding is that a BETA
version is a newly developed version with enhancements that would need checking out for a
period for any 'bugs' before it can be offered as a RELEASE version.

Other details that you requested are:-
Windows 98 installation - ADC 200 Driver V3.02, ADC 212-3 VII on LPT1, batch EJY78, Cal
date 29Apr04, pico.vxd V1.5
Windows XP installation - similar to Windows 98 but on USB-PP1 and picoopp.sys V1.2 is
mentioned in place of pico.vxd V1.5

I understand from your response that ETS is not available for the ADC 212/3 either from
within Picoscope (release or beta versions) or by using the ETS function calls. I found the
reference to these in V1.2 ADC2xx manual that was downloaded. The manual does not
remark that the ETS functions are not applicable to the ADC 212/3.

Q2A What ADC 2xx modules can use the ETS functions? (8-bit versions only?)

Q2B What is the port number for USB-PP1? (The Win XP laptop I am using has no parrellel
port.)

Re my Q5:
I will send to you some data and graphic files related to the question and perhaps you will be
able to suggest an alternative module from the Picotech range for the application# which is
beyond the maximum sample rate of the ADC 212/3. It would probably help me to answer
my own question if you could explain how Picoscope implements the 'Both channels,
alternate' setting. I suspect that what I am getting can be explained by the limit on the
update rate of Picoscope module that is not apparent on two channel analogue 'scopes.

# using a "time domain reflectometer"

Regards, Robin Smith

Hi,

Thank you for the additional information. The current stable version is 5.09.4, we are going through a stage of Beta releases and tests at the moment to produce another stable release that will become a CD release.

I have check out the problem you reported with the ETS check box and can report that this was a bug in 5.09.4 that has been fixed in 5.10.5.

The ETS mode, driver functions are only available to ADC-212/50 and ADC-212/100, both these units are 12 bits.

When the USB to parallel port is connected to the PC, it should be registered by the system and displayed as USB-PPx, where x is the number is the of adapters connected. You would select this from the dropdown menu in Picoscope. When using the function calls the port number that is passed is as follows:

USB-PP1 - 101
USB-PP2 - 102
USB-PP3 - 103
USB-PP4 - 104

There are two methods that Picoscope uses to collect data, "chop and alternative". The meaning of these are as follows:

chop: One data point is taken from channel A and then one Data point is taken form channel B. This switching between channels is continued unitl all data points are collected.

Alternative: All the data points are collected from channel A and then all the data points are collected from channel B.

I look forward to hearing from you via email.

Best regards,

Mark,

I have emailed to you this morning the information about the application that requires a faster sampling rate than the ADC 212/3 can provide.

I apologise for missing the statement in your first post about which modules support ETS - and I have only just found it in v1.2 of the Adc2xx manual (help file) that was loaded with the software installation.

Thanks,

Regards,

Robin Smith

Hi Robin,

I have recieved your email and will send you a reply ASAP.

Best regards,