LCS-1M - A Low-Cost Hobby Oscilloscope
 | |  | |  | |  | |  | |  | |  |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
The PC based user interface talks to the scope to set up the input amplifiers and the sampling
circuitry, start the data capture, transfer the data from the scope into the PC and display it there. It is
written in Visual Basic Professional V6. Below you find links to download the installer.
Rev-Ed recently released the X2 series of their Picaxe microcontroller (it was a long wait - originally
announced two years ago!). Compared to the Picaxe 28X1 the Picaxe 28X2 has a number of cool new
features, among them higher maximum clock speed (40 MHz vs. 20 MHz) and the ability to also invert
the hardware serial receive pin - this allows to get rid of the MAX232 interface and replace it with a
simple interface.
The moment I got a hold of the Picaxe 28X2 (thanks to Rev-Ed for the free development samples!) I
went and implemented a number of improvements in the firmware, PC software, and hardware. A
detailed description of the necessary hardware changes is on the Upgrade page. You need to use
the new version of the PC software together with the new version of the firmware in order to run
the modified scope!
The upgraded scopes offer a number of improvements, most importantly
Old software (for scopes using Picaxe 28X1 and MAX232 interface):
New software (for scopes using Picaxe 28X2 and simple resistor interface):
circuitry, start the data capture, transfer the data from the scope into the PC and display it there. It is
written in Visual Basic Professional V6. Below you find links to download the installer.
Rev-Ed recently released the X2 series of their Picaxe microcontroller (it was a long wait - originally
announced two years ago!). Compared to the Picaxe 28X1 the Picaxe 28X2 has a number of cool new
features, among them higher maximum clock speed (40 MHz vs. 20 MHz) and the ability to also invert
the hardware serial receive pin - this allows to get rid of the MAX232 interface and replace it with a
simple interface.
The moment I got a hold of the Picaxe 28X2 (thanks to Rev-Ed for the free development samples!) I
went and implemented a number of improvements in the firmware, PC software, and hardware. A
detailed description of the necessary hardware changes is on the Upgrade page. You need to use
the new version of the PC software together with the new version of the firmware in order to run
the modified scope!
The upgraded scopes offer a number of improvements, most importantly
- A much faster screen update rate; you need to have a sufficiently fast computer to take
advantage of that (and it only helps when the sample rate is faster than the refresh rate, about
1 msec/div and faster). On my 1.4 GHz dual-core laptop I get up to 11 frames/sec with a single
scope channel displayed, compared to around 6 frames/sec with the old version.
- Much lower noise on the signals (I discovered that the MAX232 added up to 4 LSBs of noise
onto the scope signals).
- Stabler operation at slow samples speeds (5 msec/div and slower).
- Some minor improvement to the user interface (e.g. added up/down controls and tool tips).
- Scope's power LED blinks at startup (more intuitive indication that the microcontroller is
actually up and running). Not applicable to scope version V1.0 because there the LED is
hardwired to the power supply.
Old software (for scopes using Picaxe 28X1 and MAX232 interface):
- Old PC Software (for Windows 95, 98, 2000, XP, Vista)
New software (for scopes using Picaxe 28X2 and simple resistor interface):
- New PC Software (stable version; for Windows 95, 98, 2000, XP, Vista)
- New PC Software (latest beta-version, has X-Y display mode - but use at your own risk ;-)