This software release provides a Win95 / NT interface to the BitScope
Mixed Signal Capture engine and implements single trace DSO and Logic
- Connect BitScope to a spare serial port on your PC running
WIN95 or NT.
- Make a BitScope directory on your machine and put Bitguixxx.exe in
- Run the program Bitsgui.exe (you don't need to do an install).
- Bitgui will ask you to nominate a serial port that is free.
- Turn on the display windows and press the DEMO button - you should
see a modulated sine wave.
- Press the BC ID Button and you should see BC00011x appear in the message
window on the right. - This proves communication with BitScope.
- Press the Single Shot button and you should see serial activity (back
of BitScope) and a trace with some low level noise.
- Connect a signal to a BitScope Channel and initiate a trace.
The current software displays ADC data raw. There is no filtering
or signal processing. In addition, the display algorithms track min/max
signal excursions as the waveform is collapsed. This may give an exaggerated
view of noise signals when viewing low frequncy waveforms.
The Flash ADC is 8 bits in resolution. This means that there can be
noticable staircasing of the captured waveform. It is also normal for the
ADC to dither between 2 or 3 states, so keep this in mind when increasing
the vertical resolution of the display. Try to set the attenuators to just
above the peak signal level you are capturing.
The timebase settings of BitScope are not exactly like a normal Oscilloscope.
The idea is more of capturing a section of data, then changing the way
you look at it. Also, it is currently possible to program settings that
will display invalid regions of the buffer memory, so make sure that the
PTD is set to capture eough data for your display.
In this version, Digital channel 7 is used to display the TRIG signal.
This means that you should normally use D0..D6 for logic probing. D7 may
still be used as a trigger - or as a conditional - but you will not see
its state directly. It is still recorded in sample RAM, just not displayed.
Directly displaying the Trigger level is a useful feature.
- DSO This button toggles the analog data display. This display
may be turned off if used as a logic analyzer.
- GRAT This button toggles the reference grid on the DSO
- LOGIC This button toggles the digital data display. This
display may be turned off if used as a DSO.
- POD This button toggles the analog data source from BNC to
POD. Selecting POD sample DSO signals from the DB25 POD connector.
- BC ID Requests the ByteCode ID from BitScope. Use this to
check your PIC firmware revision and also check serial operation. Note
that if you have programmed you own 4MHz PIC from the HEX file on our
web site or CCI, then you will need the 19K2 Baud version of Bitsgui.exe
- DEMO Use this button to generate some test data to try out the
BitScope UI software. This allows anyone to try the software - even if
they have no BitScope. The data generated is a 1MHz sinewave modulated
by a 200KHz sinewave, and the digital data is a counting sequence.
- TimeScale <,> Change the horizontal scale from 1nS/div
to 5S/div. Does not affect data.
- Pan <<, <, >, >> Move the position of the
data on the screen left and right.
- Trigger Position The display panels beneath the red dotted
cursors show the time position relative to the TRIGGER.
- Number of Samples The blue panel beneath the DSO display shows
the number of samples in the display buffer.
(cluster of buttons at the right of the DSO window)
- Sca Selects Volts/Div set by U/D gadgets.
- Rng Selects Attenuation settings in BitScope set by U/D gadgets.
- Offset U/D gadgets move DSO waveforms.
- Cal Clear the offset - calibrate to ADC output.
- x10 changes rang setting for x10 probe connected.
- INV inverts waveform on display - no change to data.
- CHA selects CHA (POD or BNC) as current active channel.
- CHB selects CHB
Use the buttons 0..7 to set the trigger word to match. X is don't care.
- D selects Digital signals for Trigger source.
- A selects Analog signals for Trigger source.
Initiate a trace using current settings
To abort or reprogram, just change settings and push SINGLE SHOT again.
- Sample ClkCurrent BitScope 25MHz. Adjustable later with Slow
- Sample Period Currently fixed. Later adjustable with Slow,
Expand, and SubSample.
- Capture Span Set the time period of data acquired.
- PostTrig Delay Set the time to continue sampling after seeing
a trigger. Adjustable in 10uS, 1mS, 0.1S.