Thread: Beginner!!! Please help

Originally Posted by matsp

That's probably because 0x02 and 0x08 are "invisible" in hyperterminal.
--
Mats

So, does that mean that numbers are always "invisible" to the hyperterminal by default?

Originally Posted by QuantumPete

Not at all, but you're sending ASCII code 2 and 8, which are (End of Text) and (Backspace) respectively. For two and eight you need to send ASCII codes 50 and 56 or 0x32 and 0x38 in hex.

QuantumPete

I don't have to send ASCII 0x02 and 0x08. 0x02 and 0x08 are just the data which i need to send.

Originally Posted by matsp

Yes, and unless you have a better way to "see" what you are doing, such characters will be INVISIBLE - even of 0x02 is visible (it possibly is - on a PC it's a smiley face, I think), 0x08 will be a backspace and go back so that the NEXT character written writes over the 0x02.

At this point, you may want to find a program that can log from a serial port to a file or some such, so that you can see what is ACTUALLY going on. I've written applications to do this more than once - including one that logged the traffic between a ISDN modem and it's controlling computer in both directions at once when browsing a web-site. Unfortunately, it was written for OSE, which is an embedded OS, so it's probably not much use to anyone here (should I find the source code somewhere).

--
Mats

Hello again !!!

Just to check that my function is running fine, I am now using the hyperterminal and ASC0 port.

My code is as follows:

Code:

void ASC0_send()
{
	int i,data = 0;
	unsigned char sd[] = {'W','N,'P'};
		for(i=0;i<3;i++)
	{
		data = sd[i];
		ASC0_vSendData (data);
	}
}

When I run the code, it only displays 'WP' and doesn't consider 'N'.

Am I missing something here?

Originally Posted by matsp

Is your ASC0_vSendData() not waiting if the port is busy, perhaps? Otherwise I don't know.

--
Mats

Code:

//****************************************************************************
// @Function      void ASC0_vSendData(uword uwData) 
//
//----------------------------------------------------------------------------
// @Description   This function writes a send data initialization word into 
//                the transmit buffer register.
//                
//                Note: 
//                In a multiprocessor system the master with this function 
//                has the possibility to send data to the selected slave. To 
//                achieve this, the 9th bit must set on zero.
//
//----------------------------------------------------------------------------
// @Returnvalue   None
//
//----------------------------------------------------------------------------
// @Parameters    uwData: 
//                Data to be send
//
//----------------------------------------------------------------------------
// @Date          26/11/2008
//
//****************************************************************************

// USER CODE BEGIN (SendData,1)
void ASC0_send()
{
	int i,data = 0;
	unsigned char sd[] = {'W','O','P'};
		for(i=0;i<3;i++)
	{
		data = sd[i];
		ASC0_vSendData (data);
	}
}	

// USER CODE END

void ASC0_vSendData(uword uwData)
{
  ASC0_TBIC_IR = 1;        //  reset transmit buffer interrupt request 
  ASC0_TBUF    = uwData;   //  load transmit buffer register

} //  End of function ASC0_vSendData

This is the actual full ASC0_VsendData function. Does it make more sense now?

Originally Posted by matsp

Looks like you need some sort of "wait for completion" before you send the next data item. Since I have no idea what OS you are using, etc, I can't really comment on how you should go about doing that.

Code:

  ASC0_TBIC_IR = 1;        //  reset transmit buffer interrupt request

I expect this would mean that you get an interrupt at some point later, when the transmit is "ready" to send the next char.

--
Mats

I managed to display 'WNP' entirely on the hyperterminal. The problem was with the predefined ASC0_vSendData function. New function is as follows:

Code:

void ASC0_vSendData(uword uwData)
{
  ASC0_TBIC_IR = 0;        //  reset transmit buffer interrupt request reset=0; set=1
  ASC0_TBUF    = uwData;   //  load transmit buffer register
	while (ASC0_TBIC_IR == 0); //wait till transmission finish
} //  End of function ASC0_vSendData

This code prints 'WNP' properly now.

Thanks for your help.

Originally Posted by matsp

That is a possible solution, but I would ask someone who knows more about the OS/runtime environment, because there may be a better way to "wait for an interrupt" than to poll the bit for the interrupt control.

--
Mats

But, will the way I am doing it, affect my code/hardware in any way?

I would agree, that waiting till the transmit queue is ready to accept more data is a bit overkill. Halting the OS a bit to wait is much more efficient, but a bit slower. Coming up with an optimum wait in ms's will require some testing.

This might be a stupid remark but why would you want to learn c programming when you can learn C++..... Isn't C++ better then C ? I'm really not sure so don't attack me