08M2 for my Project... maybe

[-Gary]

Greetings,
I have finished the build of my project and now for the controller.
Reading the manual and searching the Forum it looks like the 08M2 will work with 6 I/O available.

Here is the list of what I need to control with what I think will work :
1. Single Motor control thru an L293D (Forward-Stop-Reverse) = 2-Outputs (C.0, C.2)
2. Servo #1 = 1-Output (C.3)
3. Servo #2 = 1-Output (C.4)
4. Sharp IR Sensor = 1-Input (C.1)
5. Encoder Sensor (#QRD1113) =1-Input (C.5)

I have the 08 Proto Board but it uses 5 I/O. Is there a board available with 6 I/O? I saw this post from lbenson for a 6 I/O board.
http://www.picaxeforum.co.uk/showthread.php?25538

Am I looking for more than a 08M2 can deliver?

Thanks for your help!

 

[westaust55]

You will need to reshuffle your IO pin allocations to meet/match the pICAXE 08M2 capabilities.
See PICAXE manual 1 page 10
http://www.picaxe.com/docs/picaxe_manual1.pdf

C.3 can only be an input - maybe use for the "Sharp IR Sensor" and then move "Servo #1 = 1-Output" to C.1 which can be an input or output

I have not checked but as input C.5 must have a pull-down resistor as part of the circuit to hold the pin low until the DISCONNECT command has been executed will the "Encoder Sensor (#QRD1113)" circuit accept this?

 

[hippy]

Using C.5 ( Download Serial In ) input on an 08M2 has some requirements which can make it difficult to use beyond button input. It is likely much easier to go up a size to 14M2, 20M2 or 20X2 than jump through hoops to try and make things work with the smallest PICAXE chip.

 

[-Gary]

Many thanks for the replies!

I have an 08 Proto Board which is wired to control my project less the encoder. Will use that for now to develop the code.
Just received a 20M2 chip, so it will become the future processor. Looking to add LED's and maybe a speaker in the future.

 

[inglewoodpete]

I don't think that an 08M2 pin 3 (digital input only) can be used with the Sharp IR distance sensor. The sensor needs an ADC-capable input.