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NanoPc T2 how set RS323 EVEN PARITY

Moderators: chensy, FATechsupport

I have to set \dev\TTYAMA3 to 9600,even,8,1 but there isn't Parity parameters, it's fixed set to NO PARITY.

Can somenone tell me how set to EVEN PARITY?

Thanks


Raffaele Viglione
I use a JNI to do this. Here is the serial port file for you to see how it's done.

Code: Select all

/*
 * Copyright 2009-2011 Cedric Priscal
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <termios.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <jni.h>

#include "serial_port.h"

#include "android/log.h"
static const char *TAG="serial_port";
#define LOGI(fmt, args...) __android_log_print(ANDROID_LOG_INFO,  TAG, fmt, ##args)
#define LOGD(fmt, args...) __android_log_print(ANDROID_LOG_DEBUG, TAG, fmt, ##args)
#define LOGE(fmt, args...) __android_log_print(ANDROID_LOG_ERROR, TAG, fmt, ##args)

static speed_t getBaudrate(jint baudrate)
{
   switch(baudrate) {
   case 0: return B0;
   case 50: return B50;
   case 75: return B75;
   case 110: return B110;
   case 134: return B134;
   case 150: return B150;
   case 200: return B200;
   case 300: return B300;
   case 600: return B600;
   case 1200: return B1200;
   case 1800: return B1800;
   case 2400: return B2400;
   case 4800: return B4800;
   case 9600: return B9600;
   case 19200: return B19200;
   case 38400: return B38400;
   case 57600: return B57600;
   case 115200: return B115200;
   case 230400: return B230400;
   case 460800: return B460800;
   case 500000: return B500000;
   case 576000: return B576000;
   case 921600: return B921600;
   case 1000000: return B1000000;
   case 1152000: return B1152000;
   case 1500000: return B1500000;
   case 2000000: return B2000000;
   case 2500000: return B2500000;
   case 3000000: return B3000000;
   case 3500000: return B3500000;
   case 4000000: return B4000000;
   default: return B19200;
   }
}

static tcflag_t getDatabits(jint databits)
{
   switch(databits) {
   case 5: return CS5;
   case 6: return CS6;
   case 7: return CS7;
   case 8: return CS8;
   default: return CS8;
   }
}

static tcflag_t getParity(jint parity)
{
   switch(parity) {
   case 1: return PARODD | PARENB;
   case 2: return PARENB;
   default: return IGNPAR;
   }
}

/*
 * Class:     android_serialport_SerialPort
 * Method:    open
 * Signature: (Ljava/lang/String;II)Ljava/io/FileDescriptor;
 */
JNIEXPORT jobject JNICALL Java_com_axon_ax9100dg5000_SerialPort_open
  (JNIEnv *env, jobject thiz, jstring path, jint baudrate, jint bits, jint parity, jint stop, jint flags)
{
   int fd;
   speed_t speed;
   jobject mFileDescriptor;

   /* Check arguments */
   {
      speed = getBaudrate(baudrate);
      if (speed == -1) {
         /* TODO: throw an exception */
         LOGE("Invalid baudrate");
         return NULL;
      }
   }

   /* Opening device */
   {
      jboolean iscopy;
      const char *path_utf = (*env)->GetStringUTFChars(env, path, &iscopy);
      LOGD("Opening serial port %s with flags 0x%x", path_utf, O_RDWR | flags);
      LOGD("baudrate = %d, databits = %d, parity = %d, stop = %d", baudrate, bits, parity, stop);
      fd = open(path_utf, O_RDWR | flags);
      LOGD("open() fd = %d", fd);
      (*env)->ReleaseStringUTFChars(env, path, path_utf);
      if (fd == -1)
      {
         /* Throw an exception */
         LOGE("Cannot open port");
         /* TODO: throw an exception */
         return NULL;
      }
   }

   /* Configure device */
   {
      struct termios cfg;
      LOGD("Configuring serial port");
      if (tcgetattr(fd, &cfg))
      {
         LOGE("tcgetattr() failed");
         close(fd);
         /* TODO: throw an exception */
         return NULL;
      }

      cfmakeraw(&cfg);
      cfg.c_iflag = 0;
      cfsetispeed(&cfg, speed);
      cfsetospeed(&cfg, speed);
        //
        // Set the databits and parity
        //
        cfg.c_cflag &= ~CSIZE;
        cfg.c_cflag |= getDatabits(bits);       // Set bits

        if(parity > 0)
        {
            cfg.c_cflag |= getParity(parity);
            LOGD("parity selected");
        }
        else
        {
            cfg.c_cflag &= ~(PARENB | PARODD);  // Clear them
            LOGD("No parity options");
        }
        //
        // Set the stop bits
        //
        if(stop == 2)
        {
            cfg.c_cflag |= CSTOPB;              // 2 stops bits
            LOGD("2 stop bit set");
        }
        else
        {
            cfg.c_cflag &= ~CSTOPB;             // 1 stop bit
            LOGD("1 stop bit set");
        }

      if (tcsetattr(fd, TCSANOW, &cfg))
      {
         LOGD("tcsetattr() failed");
         close(fd);
         /* TODO: throw an exception */
         return NULL;
      }
   }

   /* Create a corresponding file descriptor */
   {
      jclass cFileDescriptor = (*env)->FindClass(env, "java/io/FileDescriptor");
      jmethodID iFileDescriptor = (*env)->GetMethodID(env, cFileDescriptor, "<init>", "()V");
      jfieldID descriptorID = (*env)->GetFieldID(env, cFileDescriptor, "descriptor", "I");
      mFileDescriptor = (*env)->NewObject(env, cFileDescriptor, iFileDescriptor);
      (*env)->SetIntField(env, mFileDescriptor, descriptorID, (jint)fd);
   }
   return mFileDescriptor;
}

/*
 * Class:     cedric_serial_SerialPort
 * Method:    close
 * Signature: ()V
 */
JNIEXPORT void JNICALL Java_com_axon_ax9100dg5000_SerialPort_close
  (JNIEnv *env, jobject thiz)
{
   jclass SerialPortClass = (*env)->GetObjectClass(env, thiz);
   jclass FileDescriptorClass = (*env)->FindClass(env, "java/io/FileDescriptor");

   jfieldID mFdID = (*env)->GetFieldID(env, SerialPortClass, "mFd", "Ljava/io/FileDescriptor;");
   jfieldID descriptorID = (*env)->GetFieldID(env, FileDescriptorClass, "descriptor", "I");

   jobject mFd = (*env)->GetObjectField(env, thiz, mFdID);
   jint descriptor = (*env)->GetIntField(env, mFd, descriptorID);

   LOGD("close(fd = %d)", descriptor);
   close(descriptor);
}

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