PSoC 5, 3 & 1 MCU

[Anonymous]

 I am currently working on a board designed by a professor at my university using the microcontroller CY8C29466-24PXI, this board controls 12 motors (12 8bit PWMs), has 4 LEDs, 2 switches and 1 LCD display.

   

So far, using ¨PWMs I've made the robot walk on a straight line but without control, it begins walking as the board and the power source are both ON, so I need to use the two switches to start and stop the motion of the robot, and for that we thought to use one for each action, but I don't know how to integrate the button action to the Block diagram and the main.c code.

   

Also, I've assigned LED_1 and LED_2 to ports P1_2 and P1_3 respectively, but when i try to iniciate them from the main.c, they don't appear, I begin writting "LED_1_Start();" but the code helper does not show any LED connected.

   

Thanks beforehand to anyone that could help.

[JoMe_264151 · Accepted solution]

Welcome in the forum!

   

It is always advisable to post your complete project, so that we all can have a look at all of your settings. To do so, use
Designer ->File-> Archive Project (minimal)
and attach the resulting .zip file.



Bob
 

[Anonymous]

Here it is!

[JoMe_264151]

I am using latest Designer 5.4 and the LED_1_Start() is shown in code completion (Did you switch it off?)

   

The program code looks a bit unstructured, better to use a self-written Delay() function instead of repeating the code-lines. Much better would be to use a timer, since the program could do different things until a timer fires its interrupt.

   

When you can write a function that performs a step of the robot, it would be easier to start and stop it with a button.

       

Bob

[Anonymous]

I now am able to program the start of LED1 and LED2 it may be because i didn't compile the code later, thanks.

   

About the delay, I am writting these methods:

   

void DelaySimple (void){

   

for (i=0;i<=30000;i++) {}

   

}

   

void  DelayLong(void){

   

for (i=0;i<=30000;i++) {}

   

for (i=0;i<=30000;i++) {}

   

for (i=0;i<=30000;i++) {}

   

}

   

And using them like this: 

   

PWM8_4_WritePulseWidth(11);

   

DelaySimple();

   

PWM8_5_WritePulseWidth(17);

   

DelaySimple();

   

PWM8_7_WritePulseWidth(17);

   

DelaySimple();

       

And is thowing me  5 errors and 38 warnings, can you please tell me why?, I've only coded before on JAVA  and on void methods you don't put a return.

[JoMe_264151]

your variable i is not declared within your functions.

   

and I would write

   

void  DelayLong(void){

   

uint8 i;

   

for (i=0;i<;i++) {DelaySimple()}

   

}

       

Here is a link to my favourite C-manual

       

Bob

[Anonymous]

 Bob, when you say:

   

"When you can write a function that performs a step of the robot, it would be easier to start and stop it with a button."

   

How can i read the input from Port_1_0 and Port_1_1, when the button is pressed, my professor said that in a microcontroller an interruption the reading does not have to be in the code itself, but how then can I read that interruption? I was thinking if I can use the state on P1_0 like a boolean variable, so it can be used inside an if  as the conditional,

   

i.e.:

   

while (1){

   

       int decide;

   

       if(Port1_0_Read()){

   

          //Reads when SW1 is pressed

   

         decide = 1;

   

       }

   

      if(decide==1){

   

          //Robot code here

   

        if(Port_1_1_Read()){

   

          //Reads when SW2 is pressed

   

         decide == 0;

   

        LCD_1_PrCString("STOPPED");

   

        }

   

     }

   

}

   

But in code completion does not appear that Read() command, what command is simmilar to the one I need?

[ETRO_SSN583]

When you read a mechanical switch like a push button you have

   

to debounce it. You can poll it or use an interrupt.

       

This ap note shows how to read a button. Also this shows how to use

   

shadow registers for read modify writes to the port.

               

http://www.cypress.com/?rID=2900     AN2094 - PSoC^® 1 - Getting Started with GPIO

       

https://www.youtube.com/watch?v=tei6q5M3C0g       Shadow Registers

       

http://www.cypress.com/?rID=39497     Shadow Registers

       

Link to ways of debouncing - www.dropbox.com/s/r8vfqea5fhiuzw1/Debounce.zip

       

Delay functions for PSOC 1 - www.cypress.com/

           

Regards, Dana.

[JoMe_264151]

there are two things you have to solve: the electrical and the program.

   

A Button usually connects a pin to Vdd or to GND. to the pin must be connected to the opposite using a resistor. This can be done internal to the PSoC with the pin drive mode. Additionally you ought to give the pin a characteristical name as "StartButton".

   

Then the function StartButton_Read() will give you a value of the current input pin's voltage level, High or Low, TRUE or FALSE

       

Bob

[Anonymous]

 Thanks Dana and Bob!

   

Bob, the board already came with the resistor needed  for both switches, but I don't understand when you say:

   

"Then the function StartButton_Read() will give you a value of the current input pin's voltage level, High or Low, TRUE or FALSE"

   

I have the Port_1_2 and Port_1_3 assigned as the StartButton and StopButton respectively, but when I compile it, it does not show at the main in the code completion anything similar to StartButton_Read(). What am I doing wrong?

[ETRO_SSN583]

Read of a port is done like this -

       

uint8 myport1;

   

uint8 mypin3;

       

     myport1 = PRT1DR;     //PRT1DR is a macro in Designer for port1

       

Then you use a mask to extract the pin state. For example mask for pin 3

   

(pins numbered 0 - 7 in a port) = 0b00001000 = 0x08

       

So mypin3 = ( PRT1DR & 0X08 );

       

If you wanted mypin3 to be just a logical something like this -

       

mypin3 = ( PRT1DR & 0X08 ) ? 1 : 0;

       

The ap note posted earlier shows this.

       

Regards, Dana.

[JoMe_264151]

...and to make things easier to read, thanks to the C preprocessor you may use

   

#define BitMask(BitNum) (0x01 << BitNum)
#define ReadPort(PortNo,BitNo) ((PRT ## PortNo ## DR & BitMask(BitNo))?1:0)

void main(void)
{
   
    if(ReadPort(0,3)) HandleButtonPressed();

       

Bob