Recently we released MP01A, a dual channel mixed signal oscilloscope probe adapter for Bitscope Micro.
Since then we've received requests for a more compact BNC adapter that can be used in-line to build much larger systems, especially for automated testing and data acquisition applications.
Our solution is Tom Thumb (MP02A), a low cost mixed signal adapter for use with scope probes, coaxial and other cabling.
The BNC input can be connected to CHA or the built-in waveform generator and all the other signals can be connected via the BitScope Micro Diagnostic Port (which is located behind the BNC socket). For mixed signal test & measurement, Tom Thumb provides a convenient and compact alternative to MP01A.
It's possible to connect an oscilloscope probe via the BNC socket and up to six logic and a second analog channel and/or waveform generator and clock outputs. Any passive probe with 1:1, 10:1 or other attenuation ratio can be used. It supports active differential, current or any other type of probe which is BNC terminated and designed for a standard oscilloscope. It allows the use of BNC coaxial cables for connection with other lab equipment and the pin-header behind the BNC socket can be used to connect other signals.
Tom Thumb comes into its own when building large but compact automated test or acquisition systems.
This representative example shows a 4 x 4 data acquisition array built using BitScope Micro and Tom Thumb. In this case it allows the connection of up to 16 high speed analog signals which can be captured. These signals can also be captured as logic signals with adjustable switching level comparators simultaneously. Each signal can be acquired on its own at a pre-programmed sample rate to its own high speed capture buffer. Signal acquisition can occur independently or together, synchronised via one of the logic signal on each channel via a trigger bus connected behind the front panel.
BitScope Micro itself is only 10cm wide. It's ideal to use as a single channel slice in a larger test and measurement system. We designed Tom Thumb to make it easy to build very low cost large scale systems with BNC connectivity using Raspberry Pi (and its four USB ports) together with BitScope Micro. We will be publishing some designs and new software showing how to implement network connected multi-channel test, measurement and data acquisition systems using BitScope Micro and Raspberry Pi. We also have some smaller designs for desktop use for applications where more than 2 analog channels are required simultaneously. Stay tuned!