Articles

26 Dec 2011
Soldering for Family Harmony

Santa brought the boys two Tonka Ricochet Replay R/C cars on Sunday, a blue/green one for Zane and a yellow/red one f...
21 Nov 2009
OpenWrt on Actiontec GT701-WG

Couldn’t put OpenWrt on my Goodwill Linksys WRT54G v8, but it turns out it will run on my old Qwest DSL modem, an Act...
18 Nov 2009
Linksys WRT54G v8: Ifos Fail, Wireless Bridge Win!

Pushing on with OpenWRT as a framework on which to build an Ifos server/master control program, I popped down to the ...
15 Nov 2009
TINI Disappointments

Spent some time over the weekend on an Ifos master control program targeting TINI. It’s a Java app wrapped around a t...
03 Nov 2009
Jamod Control of Ifos Successful

I am finally able to demonstrate direct jamod control of Ifos.Long story short: I built this embedded device that I w...
25 Sep 2009
Love Git, Love Gitosis

Just officially converted all my source repositories to Git from Subversion. I’ve played with Git off and on since 20...
25 Sep 2009
Gitosis Does Not Like Multiple Writable Values per Group

I spent a long time trying to figure out why this wasn’t working in my gitosis.conf:[gitosis] [group PIC]members = p...
12 Sep 2009
GeSHi Language File for PIC Assembler (18Fxxxx)

I occasionally use GeSHi on this site (via the GeSHi Filter Drupal module) to add syntax highlighting to code snippet...
08 Sep 2009
Makefiles for Use with GPUTILS

Now that I’ve switched to GPUTILS from MPLAB, makefiles have re-entered my life. I’ve always hated writing them.The l...
06 Sep 2009
Snow Leopard and ruby-serialport

As soon as I upgraded to Snow Leopard, my mastery of the hardware serial port looked decidedly unhealthy:peter@McMull...
30 Aug 2009
Controlling Ifos Using Jamod

Up to now I’ve been controlling my Ifos slaves with a simple Modbus master I wrote in Ruby. In preparation for the mo...
29 Aug 2009
Super-Effective Development Workspace

Here's my super-effective Ifos development workspace. It's a temporary solution, having no other place to put the new...
24 Aug 2009
Programming PIC from Mac OS X

My Mac OS X development tool chain for PIC is now complete. I successfully assembled my Ifos project (and by extensio...
19 Aug 2009
Migrating to GPUTILS from MPLAB

For the projects I work on these days, switching to a Mac OS X-based development environment has been mostly painless...
16 Aug 2009
Controlling Ifos from Mac OS X

More progress on my Mac development path migration: I can now control Ifos slaves from my iMac. This is the culminati...
15 Aug 2009
TINI from Mac OS X: javax.comm

I knew it wouldn’t be long before the next wrinkle presented itself. There was some frustration of the “This sh...
13 Aug 2009
TINI from Mac OS X

Still experimenting with the “master” portion of Ifos (the device itself being a Modbus slave), looking t...
01 May 2009
Circle Packing Revisited

When I originally set out to determine how many optical fibers would be supported by each Ifos lens, I discovered the...
14 Oct 2008
Non-Responsive Flash Memory

The M25P10-A serial flash memory I use in the Ifos project seemed non-responsive when installed in the actual device&...
12 Oct 2008
Ifos Hardware Check

Here's a short video of Ifos running a hardware check. The LEDs are intensely bright, so it probably would have been ...
12 Aug 2008
Successful Assembly!

I finally tracked down some sticky issues with the PCB prototype of my Ifos project. Until now, I had assumed hardwar...
10 Aug 2008
Circle Packing and Fiber Stuffing

Now that the Ifos project is nearing completion—at least, the device itself is almost ready for actual live tes...
03 Aug 2008
Debugging SPI

Compare the same SPI command sent from two PICs, one on the breadboard prototype of my Ifos project and one on the PC...
24 Jul 2008
ICSP Circuit Changes

As I suspected, the in-circuit serial programming problem I was having with the new Ifos prototypes was due to a lack...
22 Jul 2008
Ifos Assembly Attempt #2

I just started building the second Ifos prototype from scratch, and already I’ve discovered an issue that probl...
21 Jul 2008
Ifos Assembly Attempt #1

After assembling the first Ifos prototype based on the new circuit board design, I crossed my fingers and applied pow...
20 Jul 2008
Making Custom Connector Cables

My PIC programmer has a 6-pin ICSP header that I've been using to program the breadboard prototypes of my Ifos contro...
19 Jul 2008
New Boards Have Arrived

Just received my revised Ifos circuit boards from the manufacturer yesterday, so most of the evening was devoted to a...
05 Jul 2008
Not all SSOPs Are Created Equal

Iturns out making assumptions about chip variants is a bad idea.As I already mentioned, I ran into a little trouble w...
27 Jun 2008
First PCBs

Just received the first printed circuit boards for my Ifos project.I used OurPCB, which was inexpensive and fast. Boa...
08 Jun 2008
RS232-to-RS485 Converter

Since my Ifos project relies on Modbus over RS485, I needed a simple way to interface to an RS485 network from my PC ...
08 Feb 2008
Tiny Modbus Master in Ruby

Here’s a tiny Modbus master in Ruby that supports ASCII and RTU1 modes for all function (and subfunction) codes...
08 Feb 2008
Framerate Timing Resolved

I solved my timing issue, but I have to admit, I’m still confused as to exactly what caused it.My basic timing functi...
06 Feb 2008
Framerate Timing

I’ve been trying to track down an annoying timing issue in my main loop.My target is 20 frames/second (capped), which...
29 Jan 2008
RS-485 Line Biasing

Finally tracked down the source of my RS-485 communication problems, manifested by slave responses containing spuriou...
26 Jan 2008
Disable Low-Voltage ICSP

Low voltage ICSP programming mode is enabled by default on the PIC18F242. In this mode, RB5 can't be used as a genera...
11 Nov 2007
Function Pointers in PIC Assembler

Simplified the Modbus slave code by replacing the large case statements—sprinkled throughout—with function pointer ta...
25 Sep 2006
Real Code

Stashed the real code in the repository. I guess it's a real project, since only throw-away tests avoid revision cont...
25 Sep 2006
Modbus Kickoff

Set up the subversion repository and seeded it with some placeholder files, just to get the hang of things. Went to a...