New oscilloscope!
For a while now, I’ve been looking for a replacement for my ancient 50 MHz Hitachi analog scope. This scope has served me well for the 10+ years I’ve owned it, but it’s kind of a junker. Slow, out of calibration, flaky triggers… I’d could probably get a similar scope for about $15 on eBay.
As much as I love the instant response and tactile feel of analog scopes, I’ve been doing several projects lately that really could benefit from a digital scope and a logic analyzer. I’ve frustrated myself for hours trying to capture one-shot signals with my analog scope, when a digital scope would have made the job a piece of cake.
So, I finally bought a Bitscope BS100U. It’s a PC-based oscilloscope. I was initially really skeptical about PC-based scopes, but they do have a few big advantages: They don’t hog desk space, it’s easy to export data to your own tools or capture screenshots for the web, and they tend to be cheaper than a standalone DSO with similar features.
Why a Bitscope, instead of something by Pico or another of their competitors? The Bitscope is really hacker-friendly. The manual includes full schematics, their communications protocol is documented online, and there’s a free API for extending their software. Did I mention it’s cross-platform? (Windows and Linux)
Best of all, the Bitscope is a mixed-signal scope. The BS100U has two analog inputs and eight digital inputs. I’ll still need to pull out my homebrew “Saxoscope” for high-speed continuous logic capture, but the Bitscope’s MSO mode should be more than sufficient for day-to-day use.
So, I just got it in the mail today. I may post a full review once I’ve had more time to use it. My initial impressions:
Pros: Small, opto-isolated, mixed-signal, easy to set up, good build quality, fairly powerful software, open design, cheaper than a Tektronix digital scope.
Cons: Kind of slow, software UI is pretty odd, more expensive than some competing PC-based scopes ($595 without any probes/pods). Bitscope web site is very rarely updated.
(Screen shot of some mixed-signal capture from the 10 megabit SPI interface on my Propeller ethernet driver)
I just discovered ( thanks to you ) the Saxo-Q board and I’m very interested in building a high power oscilloscope with it. Do you know if it’s possible/easy to make it work with Linux? KNJN’s website is very poorly designed and it seems this project is not downhill battle. Thanks in advance
As far as I know, all the KNJN software is closed-source and Windows only unfortunately. I usually run it in a VMware virtual machine. When I was using the saxo as a logic analyzer, I’d program the board using the Windows VM, then run my own Linux software to receive the oscope data.
Could you elaborate on that? You had to program it from windows for lack of documentation or time? Thanks in advance
Well, mostly from laziness and lack of time. To use it under another OS, I’d have to rewrite the FX2 firmware and loader, since the KNJN loader is windows-only and they don’t provide source. But all the documentation necessary (FX2 and FPGA data sheets) are readily available.
At the time this wasn’t available, but I do remember seeing a Linux saxo/xylo loader that someone built since then. I don’t have a URL handy though, and I can’t find it after a few minutes of googling. Maybe you’ll have better luck?
Another useful reference is fx2pipe:
http://www.triplespark.net/elec/periph/USB-FX2/software/fx2pipe.html
This won’t program the FPGA on saxo/xylo, but it’s a handy little open source tool for streaming data between the FX2 and disk. It can also program the FX2′s firmware, and it includes some simple firmware for the FX2 that just sets up the high-speed FIFO. So if you can’t find the loader I mentioned, you might use fx2pipe’s FX2 firmware as a starting point.
Good luck!
I’ll give it a try. Thanks a Lot
hi, i’m another saxo-q guy, since having cross trained into MS .net after being electronic engineer strictly for a decade, for the past 4 years or so i have been designing / building validation engineering, verification with serial ports, parallel ports, virtual com ports, FTDI, microcontroller, and now FX2 Cypress on my saxoQ in c# .net windows application. but right now i’m between jobs so i have some time to learn cypress fx2 usb using cyusb.net.
if there are enough users, perhaps we can start a blog?
ron
everett, wa
Ron, How did you get on? Manage to start your blog?
Micah, Could you please tell me which programme did you use to get/display data on Linux?
Thanks