topic Re: 1769 - Example UART for receive in LPCXpresso IDE

1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:05 GMT

Content originally posted in LPCWare by bruno on Thu Jul 26 13:33:27 MST 2012
Hello,

I did found a example of UART for receive data...

Do I receive for function "UARTSEND"?

Can someone help me?

Thanks..

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:05 GMT

Content originally posted in LPCWare by bruno on Fri Jul 27 13:10:22 MST 2012
Someone??/

Please...

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:06 GMT

Content originally posted in LPCWare by tha on Fri Jul 27 14:08:33 MST 2012
Have you look at the sample code bundle in lpcware.com website. A lot of the sample code used the UART for send and receive.

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:07 GMT

Content originally posted in LPCWare by Superfred on Mon Jul 30 08:57:39 MST 2012
Hi Bruno,

I made an upgraded version of the UART example, using some additional receive functions and a ring FIFO RX buffer, see attachment..
I hope everything works, because this is part of a much larger project and maybe something is missing...

Here is an example code using my serial driver:

#include "serial.h"
int main(void) {
    Serial_begin(3, 115200);                                  //open UART3 with 15200 baud
    Serial_printString(3, "LPC1769 Start");            //send string
    Serial_println (3);                                             //send new line
    int x = -15;
    Serial_printString(3, "This is a number: ");
    Serial_printNumber(3, x, DEC);                                //print number
    Serial_println (3);

    Serial_flush(3);                                            //clear RX buffer
    while(1) {                                                    //main loop
        if (Serial_available(3))                              //check if RX byta available
        {
            uint8_t Sendbuf;
            Sendbuf=Serial_read(3);                            //read received byte
            Serial_write(3,Sendbuf);                            //and print it out again
        }
    }
    return 0 ;
}

Pleas tell me if it is working..

Fred

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:07 GMT

Content originally posted in LPCWare by bruno on Tue Aug 07 10:10:42 MST 2012
[COLOR=#5174a3]Superfred[/COLOR] ,

I tested your example. For send is working very well.
But for Received don't work.

Do you has more examples?

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:08 GMT

Content originally posted in LPCWare by Superfred on Wed Aug 08 04:00:54 MST 2012
Hi Bruno,

my example works if you connect your PC via an USB/Serial conveter to the LPC1769 port 3 and start a terminal emulation program like Teraterm.
Then you should see that the 1769 is echoing back all characters you type in.

To make it easier I inserted some additional commands to my program, now you can see a line with the HEX value of all received characters:

#include "serial.h"
int main(void) {
    Serial_begin(3, 115200);                                  //open UART3 with 15200 baud
    Serial_printString(3, "LPC1769 Start");            //send string
    Serial_println (3);                                             //send new line
    int x = -15;
    Serial_printString(3, "This is a number: ");
    Serial_printNumber(3, x, DEC);                                //print number
    Serial_println (3);

    Serial_flush(3);                                            //clear RX buffer
    while(1) {                                                    //main loop
        if (Serial_available(3))                              //check if RX byta available
        {
            uint8_t Sendbuf;
            Sendbuf=Serial_read(3);                            //read received byte
            Serial_printString(3, "Character received: >"); 
            Serial_write(3,Sendbuf);  
            Serial_printString(3, "<, HEX Value >"); 
            Serial_printNumber(3, Sendbuf, HEX);         
            Serial_printString(3, "<"); 
            Serial_println (3);  
        }
    }
    return 0 ;
}

But what is your application? If you use the UART to connect a GPRS Adapter or similar you must assemble the single characters Serial_read(x) gives you to a longer String (until CR/LF) you can analyse.
If you need this, I can make an example for you!

Fred

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:08 GMT

Content originally posted in LPCWare by bruno on Fri Aug 10 10:19:18 MST 2012
Hi,
I need of programme for read data and put in buffer.
I will use this programme, for read data in the GPS. As latitute and longitude.
And I will write few data in the GPS.
Only need of TX and RX, nothing else! Because the GPS there are pins of TX and RX.
Then:
- Write data and after read data and save in buffer.
If You can help me. I need much f help, for read that data.

Thank you very much

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:09 GMT

Content originally posted in LPCWare by Superfred on Sun Aug 12 07:59:09 MST 2012
Hi Bruno,

here is my example[I]:

[/I]

#include "LPC17xx.h"
#include "serial.h"
#include <stdio.h>
#include <stdlib.h>

#define RXBUFSIZE 40

char CharacterBuffer[RXBUFSIZE];
volatile uint8_t Writepos;

int main(void) {
    Serial_begin(3, 115200);  //open UART3 with 15200 baud
    Serial_printString(3, "LPC1769 Start");  //send string
    Serial_println (3);   //send new line
    printf("LPC1769 Start\n");  //sent strig to Debug Console
    Writepos = 0;
    Serial_flush(3);    //clear RX buffer
    while(1) {                                                    //main loop
        while (Serial_available(3))                              //check if RX byta available
        {
            uint8_t RxChar;
            RxChar=Serial_read(3);            //read received byte
            //printf("Character received: >%c", RxChar);
            //printf("<, DEC %d\n", RxChar);
            switch(RxChar)
            {
                case 10:
                {
                    //printf("LF Character received, Ignore it!\n");
                    break;
                }
                case 13:
                {
                    printf("CR Character received\n");
                    printf("Buffer = %s\n", CharacterBuffer);  //Print out receiced buffer
                    float val1 = atof(CharacterBuffer+2);      //Convert String to Float on position 3
                    printf("Value1 = %e\n", val1);
                    int val2 = atoi(CharacterBuffer+8);        //Convert String to int on position 9
                    printf("Value2 = %i\n", val2);
                    Writepos=0;
                    CharacterBuffer[Writepos] = 0;
                    break;
                }
                default:
                {
                    CharacterBuffer[Writepos++] = RxChar;
                    if (Writepos == RXBUFSIZE)
                    {
                        printf("RX Buffer Overflow!\n");
                        Writepos=0;
                    }
                    CharacterBuffer[Writepos] = 0;
                    //printf("Buffer = %s\n", CharacterBuffer);
                    break;
                }
            }

        }
    }
    return 0 ;

You have to enable Semihosting in your Project, see:
http://support.code-red-tech.com/CodeRedWiki/UsingPrintf

Description:I suppose that the GPS sends you a text including characters and numbers, terminated by a CR character.
My code will store this text in an Array "CharacterBuffer" with the maximum lengt of 39 (RXBUFSIZE -1).
Here I make 2 example conversions from string-numbers to Int and Float:
From position 3 upwards in the string a convertion to a float (number with digits after comma).
From position 9 upwards in the string a convertion to an int (number with NO digits after comma).
All this conversions suppose that the numbers will start always on the same position in the message. If not, please tell me the separation character betwen the numbers.

If this code is not working, uncomment the 4 //printf ... lines and send me your log output.

Please tell me if ou have questions.
PS: I attached a new version of my serial driver, the old one had a problem with buffer overflow. Please note that I coud only test UART Port 3.

Fred

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:09 GMT

Content originally posted in LPCWare by Superfred on Wed Aug 15 00:12:28 MST 2012
Hi Bruno, one more:

Debug Console printf via Semihost is very slow, so use it only if you really need it and as little as possible.

And please tell me if it is working and if you have any questions.
Fred

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:10 GMT

Content originally posted in LPCWare by bruno on Fri Aug 17 16:02:51 MST 2012
Sorry, now wich I can answer.

I test your example. Thank you very much, I liked very much him.
But, When I will receveid anything.

In Digital Analizer, I see the signal of respond.

But in programme the variables stay in zero. Don't is read anything.

[IMG]http://www.netupload.org/files/ggg6jx4nizp8zz3b3dmk.jpg[/IMG]

[IMG]http://www.netupload.org/files/zjzqb8o2k1s8dmpul8t8.jpg[/IMG]

[IMG]http://www.netupload.org/files/e3ty2b3voxgb9wq86oyh.jpg[/IMG]

Can you help again?

Please...

Thank you very much.. and excuse for delay of my answer.

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:11 GMT

Content originally posted in LPCWare by Superfred on Sat Aug 18 06:15:53 MST 2012
Hi Bruno,
it seems that you receive only one Character "DEC 0" via UART3.
This can have several reasons:

I found one problem in my code:
We am sending and then we clear the RX buffer, so we may erase the RX data.
We should do:
-Clear RX buffer at program start - Serial_flush(3);
(No more Serial_flush(3); afterwards in the code)
-Then send init command to the GPS Device.
-Then check for received data.

One other reason is can be that the baud rate setting or the Init Command to the GSM Device is wrong. Is your GPS device using Autobaud or a fixed baudrate? Can you tell me the type of the GPS Device?

To Check your code you can disconnect the GPS device and loop back the UART3 TX pin to the RX pin (via a short cable), the you should get every character you transmit back.

Fred

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:11 GMT

Content originally posted in LPCWare by bruno on Sat Aug 18 16:05:12 MST 2012
So,

Serial_begin(3, 115200); //open UART3 with 15200 baud
    Serial_printString(3, "LPC1769 Start"); //send string
    Serial_println (3);   //send new line
    printf("LPC1769 Start\n"); //sent strig to Debug Console
    Writepos = 0;
   [B] Serial_flush(3); [/B]   //clear RX buffer
    while(1) {                                                    //main loop
        while (Serial_available(3))

[B]Have I erase Serial_flush here? I don't understand, because my english is not very good.
[/B]

- The baud rate of GPS is 19200. She is already. I my tested for port serial of PC.When I started of GPS he show of data with baud rate (19200).

- I will try this. Thank you....

Just understand about Serial_flush fuction..

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:12 GMT

Content originally posted in LPCWare by Superfred on Sun Aug 19 08:06:01 MST 2012
Hi Bruno,

this is the right order for initialisation:

....
int main(void) {
    Serial_begin(3, 19200);  //open UART3 with 19200 baud
    Serial_flush(3);    //clear RX buffer
    Serial_printString(3, "LPC1769 Start");  //send string
    Serial_println (3);   //send new line
    printf("LPC1769 Start\n");  //sent strig to Debug Console
    Writepos = 0;   
    while(1) { 
.....

Serial_flush: erase everything in the receive buffer.

Fred

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:12 GMT

Content originally posted in LPCWare by bruno on Thu Aug 23 06:28:04 MST 2012
Hello, Fred

I repair the programme. It doesn't work, because baud rate is wrong. Now, is read data.

Now, It read the data receive.
But I have too many problems.

For example:
When I send this text.

TEST TEST TEST TEST TEST TEST TEST

The programme don't receive all.
It don't receive the second bit, all time when I send this test.

Is thus:

TST TEST TEST

And it can not read all data send. When I send all.

And it can not read all data send. When I send all.

So, When I send byte for byte. It receive alright.It receive all data.(I write byte for byte in the Hyper Terminal).

[IMG]http://www.netupload.org/files/obffiuhs3yv2iykehhru.jpg[/IMG]

But, When I send all byte(I imported text file for Hyper Terminal). It receive wrong. It doesn't receive second byte always and doesn't receive all data.

[IMG]http://www.netupload.org/files/e2sl6nqylhd1orpeqr3j.jpg[/IMG]

What can is happening?

Thank you very much.

Bruno Braga

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:13 GMT

Content originally posted in LPCWare by bruno on Thu Aug 23 06:35:27 MST 2012
I used LPC-Link 1769, XTAL: 12 MHz. Clock: 72 MHz.

Maybe is wrong, something in interrupt for read? I cannot find the error or something wich I am making wrong in the programme.

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:13 GMT

Content originally posted in LPCWare by Superfred on Fri Aug 24 01:16:54 MST 2012
Hi Bruno,

in the moment I cannot test it on my system because I am on holiday, so you have to wait one week.

But I don't think that it is a baudrate problem. Try to minimise the printf commands, they are slow. Use only the printf's I used in my post from 08-12-2012 04:59, this sends out only a debug info after you press return.

Or use my post from 08-08-2012 01:00 PM, this uses no printf at all.

Tell me the outcome.

Fred

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:14 GMT

Content originally posted in LPCWare by Superfred on Fri Aug 24 08:27:32 MST 2012
Hi Bruno,

I looked into the semihosting document
http://support.code-red-tech.com/CodeRedWiki/UsingPrintf
and on the bottom it says:
[I]Thus if you application uses interrupts, then it is normally advisable to avoid the use of semihosting.
[/I]So I think that is the reason why the UART receive interrupt looses some characters.
So if possible use a second UART port for print debugging info via Hyperterminal.You can use my serial library also for this, it supportsUART Ports 0,1 and 3(NOT 2).
[I]
Fred
[/I]

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:14 GMT

Content originally posted in LPCWare by bruno on Fri Sep 07 06:46:48 MST 2012
Hello, Fred!!

My programme is working perfect!!! Thank you very much .

Now, I am trying, make UART (2 PORT). I made a code, but he does not works .Could you see my programme?

Because I'm my project i need of UART2

Bruno Braga

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:15 GMT

Content originally posted in LPCWare by Superfred on Mon Sep 10 05:30:43 MST 2012
Hello Bruno,
[I]
My programme is working perfect!!! Thank you very much .[/I]
Congratulation!

UART2: the example from NXP I used as source of my serial driver contained only UART0, UART1 and UART3.

Do you really need UART2? Cant you use UART0, UART1 or UART3 instead?
On LPC 1769 you have:
P0[2]=TXD0 / P0[3]=RXD0
P2[0]=TXD1 / P2[1]=RXD1
P0[0]=TXD3 / P0[1]=RXD3

If you need UART2: what is the problem in your code? Hardfault? Not Sending? Not receiving?

UART2 is problematic on the LPCXpresso 1769 board because P2[9]= RXD2 is connected to Q3 for USB Pullup .

Fred

Re: 1769 - Example UART for receive

lpcware — Thu, 16 Jun 2016 01:41:16 GMT

Content originally posted in LPCWare by bruno on Mon Sep 10 09:10:12 MST 2012
I modified your code UART2!
The UART2, don't working.

[B]Not Sending and Not receiving.[/B]

, Bruno Braga