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output

28X1 Pin 7 (Serial Out) Used as Normal Output??

Is it possible to use pin 7 of the Picaxe 28x1, which is normally used in the download circuit, alternately as a normal output that could in my case drive a single LED? If so, what would be the code for it?

Shared microcontroller pin

A quick search here did not give me any relevant hits. So, I was hoping to ask the electronic gurus here if my plan/idea will work.

My thinking is that the photoresistor will be able to be read by the analog input and, because of the diode, the LED will not light unless the microcontroller is set as an output and set LOW.

EDIT:

Based on the input so far, I have redrawn the circuit. I hope the collective doesn't mind helping me get circuits straight.

Charlieplexing for sensors, is it possible?

I was wondering if it would be possible to use charlieplexing as a way to select sensors. If so, what is the minimum number of pins required for charlieplexing to work?

(Solved!) Low current from Arduino Output (Arduino Start Here robot)

 

EDIT: LED problem solved thanks to RobotFreak. I forgot to set the pins to output mode using the pinMode command. As RobotFreak points out, the Arduino sets all pins as inputs by default. I added a For loop to set all the pins to outputs, and everything worked great.

void setup() {
  pinMode(13, OUTPUT);  
  for (int pinindex = 0; pinindex < 14; pinindex++) {
     pinMode(pinindex, OUTPUT);  // set pins 0 to 13 as outputs
  }

SRF05 with common in/out pin

I'm trying to get the PICAXE-28x1 to work with the SRF05 usnig a common input and output pin. The reason is I want to conserve my input and output pins. I've seen discussions on this site about it, but I don't know if anyone ever succeded.

Since the 28x1 allows you to reconfigure digital inputs as digital outputs, I figured it should be possible to use "Mode 2" of the SRF05 with a commmon single input and output.

Here's the code I tried. I also tried some varations the timing, as noted.  No luck so far.

PWMOUT only on two output, that are really inputs?

Am I reading the manual (section 2, page 128) correctly? Can I only use the PWMOUT on 2 specific ports on my 28X1?

This would mean that I can't run more than two outputs with pwm, and that has to be the digital in/outs 1 and 2, so there's no hope of running it through the onboard L293D??

I must have missed something, surely there is a way around this. Pulsout maybe? I'm R'ing T. F'ing M. now, but if somebody already knows the answer, that would be helpful..

 

 


EDIT:

 

messing with the motor outs (A and B)

Just a thought:

(lets call the four motor outputs A1, A2, B1 and B2)

What would happened if I connected a GM10 (with the original spring still attached) between B2 and A2? Like in the illustration below

motorhead.jpg

I was hoping to achieve the following: