Archive for July, 2012

More of the same …

Posted in The Downside of software development on July 29, 2012 by asteriondaedalus

The saga of getting over the newbie hump with the Synapse SNAP goes on.


The issue with the RF255PC1, not being detected by Portal software, while it sat in the DFRobot USB dongle is now likely because the RF266PC1 is precanned with AT modem mode and not MESH per se.  Apparently if you run “Erase SNAPpy Image” on the RF266PC1 it will fall back into MESH mode and might have been used as the PC node.  Well that was one thought someone offered, someone else suggested it was that there were a list of XBEE USB dongle that would work with Portal and the DFRobot XBEE USB dongle wasn’t one of them.  That mystery can stay as a mystery.

The problem I had next was using the RF200PD1, sitting on the SN132 SNAPstick USB module, as the PC node.  I downloaded code to talk P2P with an RF266PC1 sitting on an Arduino but fell foul of the fact that Portal does not recognize the USB port, it has to be a COM port, for use when erasing the SNAPpy Image.

Turns out you should download VCP (virtual comm port) drivers from Silicon Labs for the USB chip on the SN132 before you start using Portal.  Not really written down in one place (hidden in user groups or on loose internet pages).

Next problem, the erase hangs, waiting for you to restart the module.  Go figure, the SN132 SNAPstick USB module has no RESET button.  Luckily the RESET (pin 23) is sitting next to the GND (pin 24).  I took the chance and shorted it.  Most likely if it didn’t work, and I fried the module, it would be cheaper to by another module as most of the supporting board options were expensive.

In any event, I am but up in MESH mode but will look at soldering a small reset button onto the SN132 so I can recover the PC node if I ever load another script that breaks it out of MESH mode.

Pin compatible but …

Posted in The Downside of software development on July 14, 2012 by asteriondaedalus

Well, went to try out the Synapse XBEE replacements (SNAP).  Unfortunately I had assumed that I could plug the base node into my PC via the DFRobot XBee USB V2 I had in my drawer.  It was the first time I had dusted it off so first sign of a problem was that the driver installation failed with an Error 10 (driver didn’t start).  When the USB dongle is connected to the computer, Windoze assigns it a COM port but obviously assigns the wrong drivers.  I have posted on the DFRobot user group to see if someone else had solve the problem.

In any event, decided (begrudgingly) to order a Synapse USB dongle board for the base node – just to be on safe side.



The USB dongle is not an XBEE format.  The Synapse site says it fits “all” their modules – it should have said “all but the XBEE format” modules.  I ended up having to order a RF200PD1 module which is the Synapse propriety format.  The RF200PD1 will talk to the RF266Pc1 XBEE foot-print format modules so this isn’t an issue.  The confusion on the site on what mates with what is.



Synapse have updated their site to clarify that there is a difference in form factor between the two models so you aren’t misled by the use of “all”.

Parallax Propeller 2 Killer

Posted in Hardware on July 7, 2012 by asteriondaedalus

Not a few years ago I was working in on a real-time acoustic system for chasing submarines that introduced me to the Inmos Transputer.  Basically it was a hardware based parallel computing platform with a parallel programming language.  It was, ahead of its time.  Parallel programming couldn’t really find a niche in those days, no problems big enough.  However, nowadays we have Clusters, Grids, MPI, multi-core and things to do with that power.


The XMOS  comes from the stable that was Inmos and tries to succeed where the transputer failed.  The transputer’s clock speed was always woeful and DSP and RISC chips that were coming out soon surpassed them for speed.  Their main strength remained being based upon the CSP model (in hardware) and allowing multiple CPU to be linked together to add the computing power you needed. (One of first table tennis play robots was based on a transputer system).

Now, the upshot.  The XK-1A development board I ordered turned up.  The first thing will be to download a few examples to buzz out the development environment.  The next thing will be to look at porting some of the IMU/AHRS and AutoPilot code.  The chip is a single-core digital device for DSP, interfacing and general processing tasks with:

  • Up to 500 MIPS
  • Up to 8 threads
  • 64KB SRAM
  • Up to 64 I/O pins

Remember the Parallax Propeller, the closest comparison in terms of architectural style, is 20 MIPS per cog, or 160 MIPS in total for an 8-cog Propeller.

Note there is a dual an a quad core XMOS chip if the single core isn’t enough (1ooo MIPS and 1600 MIPS).



It occurs to me there is an error in my discussion above. Can anyone see it?

MSN, User Community, and that joke about the hot air balloon

Posted in The Downside of software development on July 1, 2012 by asteriondaedalus

Community help.  Is it?

More often than not, no.

Go figure if you don’t pay for it you get what you pay for.

Had a problem with a couple of builds from other sources.  The developers used CMAKE and banked on you having MS VC++.

Now there have been a few software downloads that rely on MS VC++ and so I ended up variously with v5, v8, v9 and v10 dependencies.  32bit and 64 bit.

Problem, the license management of ms development products sux and so I hit a wall when I had V10 IDE working fine but the thing wouldn’t work from command line – reporting license expired.  That is, I narrowed it down to the multiple versions of MS VC++ interacting.

No matter I thought.  I would ask the friendly goons at MSN the friendly Microsoft community.

Some dweeb basically panned me for using CMAKE and basically said I was on my own.  The problem for the dweeb was that the whole reason MS have released free development tools IS THE OPEN SOURCE COMMUNITY.


I get it dweeb.

You had your 15 minutes as a supporting actor in Gamer but now you feel unrecognized.  We recognize you.