For reference, the 50 MHz version is about $400. The Rigol, of course, could also decode that UART string, a feature none of the other scopes here could match. Naturally, a single event trigger would work too. By using normal triggering (instead of auto) the display nice and stable: The UART is slightly more challenging since it sends a burst of data with a long gap in between.
The LPC812 cycles this output from 0 to 100% fairly quickly and I happened to catch it at that point. In this case, the PWM was at nearly 99% (you can read that out at the bottom of the screen).
As you’d expect, it was easy to capture the signals on this scope. To get an idea of what the signals ought to look like, I measured them both with my current favorite bench scope, a Rigol DS1104Z.
Smartscope oscilloscope review serial#
So I stuck with two different test signals: a varying pulse width modulation signals and a serial UART transmitter. The Labtool’s demo CPU generates a lot of different signals, but with only one channel on the test scopes, it didn’t make sense to look at, for example, I2C data. The idea is you can use the Labtool in a classroom with no additional equipment. The board also has a cheap ARM processor (an LPC812) on it that serves only to generate test signals.
However, I’m not using any of that capability for now. It is an LPC-Link programmer attached to an LPC ARM board that has several high-speed A/D channels. This is an interesting board in its own right. To make that easy, I grabbed yet another scope-like thing I had handy: an Embedded Artists Labtool. This time, though, I wanted actually to look at some real-world signals. Both of the devices cost about $100, and both have their plusses and minuses. Last time I introduced you to two relatively inexpensive and somewhat portable scopes: the EM125, which is a cross between a digital voltmeter and an oscilloscope, and the Wave Rambler, which is a scope probe with a USB connector attached.
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