buy those for $15-$20, but you’ll still have to
hack their connectors into a three-pin male
to plug into the breadboard. For a bit more
hacking, you can make your own and save
some bucks. Silicon Lab’s CP210x (also
CH340) adapters are widely available for a
dollar or two and work great with Windows
8, but they need their signals inverted. Avoid
Prolific’s 2303 adapter — a no-go for Win8
and later. PICAXE forum member, Goeytex
shows how to add a 74HC14 inverter in the
schematic in Figure 4.
Having made many of these, I can
say the quickest one to wire up is the
white CP2102 board shown in Figure 2
using the chip-centric diagram in Figure
5. Three CP2102 connections line up
perfectly with the 74HC14, making for a
simple solder job on a small perfboard
scrap.
End up with three male pins pointing
down per Figure 5. These pins fit into the
breadboard. I glue a small plastic strip on
the back of the perfboard as a polarizer
to help align the pins with the top edge
of the breadboard. You can also use a
servo extension cable if desired to
connect the USB adapter to the
breadboard some distance away.
Download CP2102/CP210x VCP
drivers from
www.silabs.com/products/
mcu/Pages/USBtoUARTBridge
VCPDrivers.aspx and use the Device
Manager to verify operation and COM
port number. Download the PICAXE
Editor v5.5 from
www.picaxe.com/
Software/ PICAXE/PICAXE-Programming-Editor. Run the Editor
and watch for the OPTIONS dialog box
(click the OPTIONS button on top if
necessary); see Figure 6. Click Serial
Port, select your adapter’s COM port
number 1-15, and click APPLY.
➤ Moment of Truth
Now, plug the USB adapter into
your breadboard (watch those pins!)
with the power switch off. Still in the
OPTIONS dialog box, click MODE, select
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