Arrival
One afternoon when I went to the mailbox to pick up the mail I was surprised to
find a package from Circuit Cellar that had a WIZnet WIZ810MJ module inside. Everyone
else that I'd read said they got an e-mail telling them the module was on the way,
I didn't get the e-mail so I wasn't really prepared to have the module arrive.
At first glance the WIZ810MJ looked like it would be easy to use, all the control
pins for the W5100 are brought out to a pair of connectors on the side. But that
was only at first glance.
More and more electronics are coming in smaller sizes, and the WIZ810MJ is no exception.
The connectors on the module are a double row of 2mm pins. The double row makes
it impossible to plug into a breadboard, and the 2mm pitch doesn't fit with the
standard .1-inch spacing used by breadboards. While this makes the WIZ810MJ compact
-- and it takes up less real estate on a board, it also makes it next to impossible
for a hobbyist to simply plug it in.
Fortunately for me, this was a problem that was recognized early in the contest
and NKC Electronics created a breakout board that converts the 2mm pin headers to
a row of .1-inch spaced pins suitable for plugging into a breadboard. The breakout
board only brings the pins required to run the W5100 in SPI mode, but that's perfect
for interfacing with the Picaxe.
The SPI adapter comes as a kit, and that led me to my next problem. My trusty old
soldering iron doesn't have a fine enough tip to solder those itty bitty 2mm pins
without making an excessive number of solder bridges. One day while I was hanging
around I headed off to the Radio Shack off 132nd in the Silver Lake area. After
about 5 minutes of wandering around the store I was afraid I was at the only Radio
Shack in the world that didn't carry soldering irons. I waited patiently while the
clerk helped the two sorority sisters find a new power cube for their DVD player,
and then finally had to ask where the soldering irons were. 2 minutes and $8.99
poorer I had a fine tipped soldering iron to use to assemble the new SPI adapter.
Assembly of the NKC Electronics adapter board went smoothly, with only two small
problems. It wasn't clear from looking at the circuit board which direction the
LEDs installed in the holes, but by tracing the wires out I figured that out easily
enough. The other was really dumb. I reached for the new soldering iron without
looking. Since it's just slightly different than my old one I missed the handle
and grabbed the iron. I only got one smally 2nd degree burn on the end of my finger
-- it only hurts when I type...
The only remaining issue was coming up with a 3.3-volt power supply to run the WIZ810MJ
module. Because I wasn't prepared for the module to arrive I didn't have the bits
I needed to put together a power supply. I searched around for a supplier and came
up with Kronos Robotics, so that's where I bought the 78L33 linear voltage regulator
that I needed (two, just in case). I picked up some other bits to round out the
order, but it ended up costing me almost as much for shipping as it did for the
components. I bit the bullet and wrote the check.
What with one thing an another, it took me almost two months to get the bits together
that I needed to make the WIZ810MJ interface with my Picaxe. Now that I had all
the bits rounded up, I was ready to start working on connecting the WIZ810MJ to
my Picaxe. But that's a different article.