Installation guide

PicoScope 4000 Series (A API) Programmer's Guide 17
Copyright © 2008-2014 Pico Technology Ltd. All rights reserved. ps4000apg.en r1
3.7
Timebases
The API allows you to select one of 2
32
different timebases created by dividing the
oscilloscope's master sampling clock.
Timebase (n)
Sampling interval (t
S
)
Sampling frequency (f
S
)
n
12.5 ns × (n+1)
80 MHz / (n+1)
0
12.5 ns
80 MHz
1
25 ns
40 MHz
2
32
–1
~54 s
~18.6 mHz
3.8
Combining several oscilloscopes
It is possible to collect data using up to 64 PicoScope 4000 Series PC Oscilloscopes at
the same time, depending on the capabilities of the PC. Each oscilloscope must be
connected to a separate USB port. The ps4000aOpenUnit function returns a handle
to an oscilloscope. All the other functions require this handle for oscilloscope
identification. For example, to collect data from two oscilloscopes at the same time:
CALLBACK ps4000aBlockReady(...)
// define callback function specific to application
handle1 = ps4000aOpenUnit()
handle2 = ps4000aOpenUnit()
ps4000aSetChannel(handle1)
// set up unit 1
ps4000aRunBlock(handle1)
ps4000aSetChannel(handle2)
// set up unit 2
ps4000aRunBlock(handle2)
// data will be stored in buffers
// and application will be notified using callback
ready = FALSE
while not ready
ready = handle1_ready
ready &= handle2_ready
Note: It is not possible to synchronise the collection of data between oscilloscopes that
are being used in combination.