Do's and Dont's of a PICAXE
1. NEVER supply
a voltage over +5.5VDC, not
even +5.6VDC, to a PICAXE!!
The closest you can get, is to use
rechargeable-- Four AAs, output
whereas Four standard AAs will output
is used, it's output should be set to +5.0VDC
2. Manual #1 on page
#8 shows the typical setup
between the PICAXE and the,
(USB or Serial cable) that plugs into a 3.5mm
mounted on your project board.
Their are two
resistors, 22k & 10k that make up the network going to the
Leg of the PICAXE.
Cable. It doesn't always work due to the levels com-
board that will fix this
problem. The newer Laptops seem to have this problem the most.
the opposite of us in the USA. A 3-pin
is a screen shot of my enhanced version for the Programmer / interface.
need to program. You
will only need
one resistor and a shunt-jumper after the Programing Cable is removed.
advanced setup for programing
PICAXE. This is much more stable then
the circuit on page #8. I will keep this
page up to date; the 3 manual's have also been
updated. The new 18M2, 14M2,
20M2 and the 08M2 chip's has been released and have
Manual #1 & #2 have been updated, again to
reflect these changes: July 2011.
PICAXE that has a "Reset" line), to place a
4.7k resistor between +5VDC and
the Reset line. Leaving it "floating"
may give unknown results. If you don't
have a 4.7k Resistor, you may substitute with
a Resistor value up to 10k. This
true for the 08M & 14M. There
is no Reset line. Power-OFF, wait a
couple of seconds, turn it back ON, this
will put you back in business. You
can always re-download the code as well.
If it still does not reset the 08M
or 14M, then pull the power cable to your
project, start the download, then
apply power once again to your project. The
has always worked for me.
5. Please note that the 28X2 and the 40X2 Power Legs handle any
between +2.1VDC and 5.5VDC. This is also
true of the M2
class of PICAXE.
Page 6 - EMF and how to get around it.
Page 7, 16 - ULN2003(A) 16-Pin, ULN2803(A) 18-Pin.
Page 8, 12 - Using IRF5xx or IRL5xx components to drive a
Page 8, 14 - Interfacing to a Relay.
Page 9 - Driving LEDs.
Page 10 - Driving a Light Bulb or Buzzer.
Page 11 - Piezo Sounder or 40Ω Speaker. Caveat: A 10uF
tor goes to the
OUT PIN of the PICAXE. The negative side
goes to the "+" side of the Speaker, and the
the Speaker goes to Ground.
Page 12 - A Solar Motor, (or a Toy Motor in general), should have
Page 13, 18 - Using an L293D, (or L393), are used to drive 2-motor
L298 should be here also.)
Page 15-16 - Working with Unipolar Stepper Motors.
Page 17, 18 - Working with Bipolar Stepper Motors.
Page 19 - Interfacing with Servo Motors. Note the Capcitor &
Page 20 - Working with Counter Modules.
Page 21-23 - Using 7-Segment LEDs.
Page 24 - How to control Solenoids.
Page 25 - Smart Wire
Page 26-27 - Switches, (Reset, Noise, Debounce-- noisy contacts.)
Page 28 - Working with POTS, (Potentiometers.)
Page 29 - Using LDRs, (Light Dependant Resistors.)
Page 30 - How to wire a Thermistor.
Page 31-42 - Working with LCD Displays.
Page 43-46 - Interfacing to a PC, (Computer), via Serial connection.
Page 44 - MAX232 Serial Interfacing.
For some reason, the following are missing in
Manual #3 v4.4 -------------
Page 45 - Enhanced Serial Circuit. (see my schematic above for details).
that is needed to program a PICAXE.
Page 49 - Hard-Reset
Page 69 - Digital In, Digital Out, Analogue.
Page 76 - Making Sounds: Buzzer, Piezo, Speaker.
Page 77 - Switches.
Page 78 - LDR (Light Depandant Resistor).
Page 79 - DS18B20 Temperature reading device. Use a pull-up
the output of the DS18B20 and VDC.
Page 83 - Using Interrupts
Page 105 - FAQ's
I2C is a 2-PIN connection between the PICAXE and the I2C device(s).
Both lines should have a 4.7K resistor from the SDA and SCL lines
and connected to VDC at the other end of the resistor's. Only need this
ONCE on each LEG, no matter how many I2C devices are connected.
See page #6 of the AXE033.PDF manual.
1-Wire devices-- there should be a 4.7k resistor between DQ LEG and
Also see this link to FAQs here
Here is a breakdown on the LEG/PIN
assignments of an 08M.
This will be true for any PICAXE, but will have other LEG/PIN
So a LEG is the physical Leg on the device; where as
the PIN has the assignment for what ever feature it can handle on
the LEG. Below is an explanation of how this is done with an 08M.
Ok, let's look at the facts--
we will use the 08M on the
1. Currently there are I/O lines
that do not
necessarily match the same physical LEG to the
same use of
that device. (i.e. On an 08M Physical
LEG 3, is an IN/OUT PIN 4).
2. According to Manual #1, pg 27
also be hooked-up to the 22k & 10k according the the diagram on that
3. Physical LEG 4 is Strictly an IN PIN 3 (i.e. use a switch to trigger
4. Physical LEG 7 serves two purposes. OUT 0 and SERIAL OUT (output
Serial OUT is
sent back to the PC, and with the 'debug command', you can
Computer Monitor to see what is happening. This PIN also is used
'Program Editor' to let it know that the PICAXE programmed correctly.
(Also note on pg #45 that 180Ω resistor is added. Good practice.)
5. LEG 6 is IN/OUT PIN 1 plus it can be
used for ADC circuits.
6. LEG 5 is IN/OUT PIN 2
7. LEG 4 is INPUT PIN 3
8. LEG 3 is IN/OUT PIN 4
So let's recap:
LEGS 7, 6, 5, 3
6, 5, 3 are INPUTS
Notice that LEG 6, 5, 3 are
the TRUE I/O PINS.
are NOT an option
even if running
is a good practice and it won't
cost but pennies to do so!
Might as well take care of noise
and one less thing to be concerned about.
One more item, when the
, take a
from LEG 2
to J1 then
This has cleared up more then
once, spurious problems hardware people have found.
Hope this helps out, fellow NEWBIE
Copyright © 2008- Ted J. Mieske
All Rights Reserved.