[En-Nut-Discussion] CR + LF or LF + CR

[Andre Riesberg]

Ulrich Prinz wrote:

>Sorry to fast...
>But by the way: I stumbled accross that on another project: Windows has 
>a big problem with string recognition with exchaned CR/LF. We searched 
>for hours to find that on a test enviroment in a production line...
>
>Ok, here are fixes for the different platforms. Tell me what you tested 
>and what worked, so I test the others.
>
>static void DebugPut(CONST NUTDEVICE * dev, char ch)
>{
>     if (ch == '\n') {
>        while ((inr(dev->dev_base + US_CSR_OFF) & US_TXRDY) == 0);
>         outr(dev->dev_base + US_THR_OFF, '\r');
>     }
>     while ((inr(dev->dev_base + US_CSR_OFF) & US_TXRDY) == 0);
>     outr(dev->dev_base + US_THR_OFF, ch);
>}
>
>The wait for the THR getting empty has to follow after sending the CR 
>out. Sorry again.
>
>Ok, here the fix for AVR: arch/avr/dev/debug1.c
>Find / replace DebugPut(char ch)
>
>static void DebugPut(char ch)
>{
>     if(ch == '\n') {
>        while((UCSR1A & BV(UDRE)) == 0);
>        UDR1 = '\r';
>     }
>     while((UCSR1A & BV(UDRE)) == 0);
>     UDR1 = ch;
>}
>
>And for AVR debugging via UART 0: arch/avr/dev/debug0.c
>Find / replace DebugPut(..)
>
>/*!
>  * \brief Send a single character to debug device 0.
>  *
>  * A carriage return character will be automatically appended
>  * to any linefeed.
>  */
>static void DebugPut(char ch)
>{
>     if(ch == '\n') {
>        while((USR & BV(UDRE)) == 0);
>        UDR = '\r';
>     }
>     while((USR & BV(UDRE)) == 0);
>     UDR = ch;
>}
>
>And now for the LPC2xxx: arch/arm/dev/debug_lpc2xxx.c
>
>/*!
>  * \brief Send a single character to debug device 0.
>  *
>  * A carriage return character will be automatically appended
>  * to any linefeed.
>  */
>void DebugPut0(char ch)
>{
>   if(ch == '\n') {
>      while ((U0LSR & U0LSR_THRE) == 0);
>      U0THR = '\r';
>   }
>   while ((U0LSR & U0LSR_THRE) == 0);
>   U0THR = ch;
>}
>
>/*!
>  * \brief Send a single character to debug device 1.
>  *
>  * A carriage return character will be automatically appended
>  * to any linefeed.
>  */
>void DebugPut1(char ch)
>{
>   if(ch == '\n') {
>      while ((U1LSR & U1LSR_THRE) == 0);
>      U1THR = '\r';
>   }
>   while ((U1LSR & U1LSR_THRE) == 0);
>   U1THR = ch;
>}
>
>Andre Riesberg schrieb:
>  
>
>>Hi all,
>>
>>I use the debug output via serial interface. In the output every LF will 
>>be replaced by LF CR.
>>This surprised me a little bit, many other system (I know) use CR LF.
>>
>>I know this is really an unimportant detail but my favorite terminal 
>>program can suppress CR LF but not LF CR on the screen.
>>
>>Greetings
>>Andre
>>
>>PS: I forward this mail to the developer of HTerm. Maybe in the next 
>>version he can also suppress LF CR :-)
>>
>>_______________________________________________
>>http://lists.egnite.de/mailman/listinfo/en-nut-discussion
>>    
>>
>_______________________________________________
>http://lists.egnite.de/mailman/listinfo/en-nut-discussion
>
>
>  
>
Hi Ulrich,

thanks for your answer! Too bad to spend hours for a detail....

In the moment I have no ARM board avail, but the source looks correct.

In the AVR debug1.c and debug0.c I exchange to  line of code:

Original:
/*!
 * \brief Send a single character to debug device 0.
 *
 * A carriage return character will be automatically appended
 * to any linefeed.
 */
static void DebugPut(char ch)
{
    while((USR & BV(UDRE)) == 0);
    UDR = ch;
    if(ch == '\n')
        DebugPut('\r');
}

Modified:
/*!
 * \brief Send a single character to debug device 0.
 *
 * A carriage return character will be automatically appended
 * to any linefeed.
 */
static void DebugPut(char ch)
{
    if(ch == '\n')
        DebugPut('\r');
    while((USR & BV(UDRE)) == 0);
    UDR = ch;
}

Bye the way... I am beginner with Nut/OS (less then 1 week). What is the 
correct way to make this changes permanently? I had also found an issue 
in "cfg/arch/porttran.h" that prevents my 1-wire interface to work 
correctly. So long this modification is not in the common code base, 
nobody can use my interface.

Greetings
Andre