24FJ256 SPI链接到实时情节不顺利

我使用24FJ256GB206通过SPI1读取一个单独的16位AD转换器，每8毫秒转换一次。我正在读取HyByter，LoBooad，并将这些写入SD卡——SPI2-I也读取状态字节，但丢弃它。随着每一关，我也通过SPI3（主模式）发送16位值到从模式的一个32 MX764 F128L的SPI3。我使用手动GPIO作为我的SS（或CS）。应该发生的是，32 MX读取传入的“实时”16位数据，并将其绘制在7“TFT显示器上”，它也从SD卡中检索相同的存储数据，并在同一屏幕上绘制垂直分离的数据。D数据正在被成功地绘制，但是我还不能得到实时数据来绘图（我只得到一个水平的直线：请在这里看到显示图像）。首先我从24FJ检查SPI3主控器，当在一个循环中发送0xAAAA时，它工作得很好（请参阅范围输出）。然而，当我发送实时数据（每8ms 16位）时，我得到了一个相当讨厌的输出，输出时钟失真，输出有时保持高电平（或者，如果最后一位高，这是正确的吗？）显然，SPI3没有问题，它发送了0xAAAA，没有麻烦——在上面的代码中必须有一些坏的东西——SPI3CON1被设置为0x043E（16位，活动到空闲，主控，2MHz），并且我确认了我的手动SS（CS）正在工作。请注意，我每次写入总共3×512字节（3）。* 512/2个16位值。SD卡和其他两个SPI工作正常。32 MX端可能有问题，但我想确保24FJ工作正常。首先，您的想法赞赏。



      以下为原文

    I'm using a 24FJ256GB206 to read a separate 16 bit AD converter via SPI1 with one conversion every 8mS.
I am reading hibyte, lobyte and writing those to an SD card -  with SPI2 - I also read the status byte but discard it. With each pass I am also transmitting the 16 bit value via SPI3 (master mode) to a 32MX764F128L's SPI3 in slave mode. I am using a manual GPIO as my SS (or CS).



int plotSECTOR( LBA a)
// a LBA of sector requested

// returns TRUE if successful
{
    unsigned int r, i, p, q;
   

AD_ON;//enable AD converter (working fine)
    r = sendSDCmd( WRITE_SINGLE, ( a << 9));
writeSPI( DATA_START);

  
        
        for( i=0; i   {
  while(AD_READY);//16 bit AD converter 8mS cycle - this goes low when ready
  writeSPI(p=readSPI1());//write to SD card 8 hi bits NOTE: SPI2 is for SD card works fine
  writeSPI(q=readSPI1());//write to SD card 8 lo bits
  readSPI1();//read 8 status bits (discard)
  _LATG7=0;//enable slave SS/CS line
  writeSPI3(p<<8|q);//assemble 16 bits and write to 32MX slave
  _LATG7=1;//disable slave
  }
   // send dummy CRC
  writeSPI(0xFF);
     writeSPI(0xFF);
        // check if data accepted
        if ( (r = readSPI() & 0xf) == DATA_ACCEPT)
        {
            for( i=0xffff; i>0; i--)
            { // wait for end of write
                if ( (r = readSPI())) break;
            }
        } // accepted
        else
            {r = FAIL;B3;while(1);}

    //} // command accepted

    // remember to disable the card
    AD_OFF;
disableSD();
    return( r); // return TRUE if successful

} // plotSECTOR
What is supposed to happen is that the 32MX reads the incoming "real time" 16 bit data and plots it on a 7" TFT display - it then also retrieves the same stored data from the SD card and it plots that on the same screen -separated vertically.
The retrieved SD data is being successfully plotted but I can't yet get the real time data to plot (I just get a horizontal straight line: please see display image here).
First I checked SPI3 master from the 24FJ and, when in a loop to send 0xAAAA, it works fine (please see scope output). However when I am transmitting the real time data (16 bits every 8mS) I get a rather nasty looking output with misshapen clock pulses and an output which sometimes remains high after transmission (or is this correct if last bit high?)
There is obviously no problem with SPI3 which sends 0xAAAA with no trouble - there has to be something bad in my above code - SPI3CON1 is set to 0x043E (16 bit, active to idle, master, 2MHz) and I have confirmed my manual SS(CS) is working.
Please note I'm writing a total of 3*512 bytes each time (3*512/2 16 bit values).
The SD card and the two other SPIs are working fine.

The 32MX end may have a problem but I want to be sure the 24FJ is working OK first.

Your thoughts appreciated.
   Attached Image(s)

0