Never succeed in transmitting ethernet packet (in *.xc)!

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jerryXCORE
Experienced Member
Posts: 65
Joined: Tue Apr 30, 2013 10:41 pm

Never succeed in transmitting ethernet packet (in *.xc)!

Postby jerryXCORE » Tue Aug 06, 2013 6:17 pm

Hi, all:

I am testing with XC-3 Board. I never succeeded in transmitting an Ethernet packet in ".xc" file, using syntax:
outPort <: packet

But I can transmit the packet in assembly file "*.s", using syntax:
out res[r0], r1

So, is it possible to do the packet transmission in ".xc" file?
Or we always need to use assembly file "*.s"?


Thanks
Jerry
User avatar
JasonWhiteman
Active Member
Posts: 63
Joined: Mon Jul 15, 2013 11:39 pm

Postby JasonWhiteman » Fri Aug 09, 2013 2:10 pm

Perhaps more context in terms of surrounding code w/full text would help illuminate the issue.

Regards,
Jason Whiteman
jerryXCORE
Experienced Member
Posts: 65
Joined: Tue Apr 30, 2013 10:41 pm

Postby jerryXCORE » Fri Aug 09, 2013 10:32 pm

Thanks, below is the function I used in my project:

*I just copy codes from "sc_ethernet" at github.com/xcore

*Basic operation of my project:
-My PC send an packet to XC-3 board
-XC-3 should reply with a random preset packet
-(I am testing EtherCat packet, but the exact packet is actually not relevant)

*packet[80] and txbuf[20] are same content
- packet[]: 8-bit char array (future testing, good for EtherCat)
- txbuf[]: 32-bit int array (currently testing!!!)

*The project compiled and run OK, but:
- XC-3 received the packet
- but not packet received at PC.

You can focus on 20 line of codes between while(1) and switch (tail_byte_count):
-- Above while(1): create a packet
---After switch (tail_byte_count): CRC calculation

----------------- codes below -----------------------------------------------------------------

Code: Select all

void packetTxD( chanend c_out, out buffered port:32 p_mii_txd)
{
	register const unsigned poly = 0xEDB88320;
	unsigned int crc = 0, idx, word_count = 20;
	unsigned int word;
	unsigned int txbuf[20];
	int tail_byte_count = word_count & 3;
	char packet[80] =    { 0x00, 0x22, 0x97, 0x00, 0x10, 0x2b, 0x68, 0x05, 0xca, 0x15, 0xbd, 0xa7, 0x88, 0xA4, 0x38, 0x10,
        //---------------------- -----------------------                         ----------------------
         0xb9, 0xb2, 0xb6, 0xc4, 0xbb, 0xe1, 0x68, 0xa5, 0xca, 0x15, 0xbd, 0xa7, 0xa9, 0xfe, 0x5f, 0xf8,
        //---------------------                          ----------------------  -----------------------
		  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xa9, 0xfe, 0x46, 0x7a, 0xaa, 0xaa };
       //----------------------
	for(int i=43;i<73;i++)			packet[i]= (i+2);
	for(int i=73;i<80;i++)			packet[i]= i;
	for (int i = 0; i < 80; i++)	(txbuf, unsigned char[])[i] = packet[i];


	while(1)
	{
		chkct(c_out, 1);crc=0;
		printstrln("       start.txd..");
		idx=0;
		p_mii_txd <: 0x55555555;
		p_mii_txd <: 0xD5555555;
		word = txbuf[idx];
		#pragma xta endpoint "mii_tx_first_word"
			p_mii_txd <: word;
			idx++;
			crc32(crc, ~word, poly);

			do {
		#pragma xta label "mii_tx_loop"
				word = txbuf[idx];
				idx++;
				crc32(crc, word, poly);
		#pragma xta endpoint "mii_tx_word"
				p_mii_txd <: word;
			} while (idx < word_count);

			switch (tail_byte_count)
			{
				case 0:
					crc32(crc, 0, poly);
					crc = ~crc;
		#pragma xta endpoint "mii_tx_crc_0"
					p_mii_txd <: crc;  printhexln(crc);
					break;
				case 1:
					word = txbuf[idx];
					crc8shr(crc, word, poly);
		#pragma xta endpoint "mii_tx_final_partword_1"
					partout(p_mii_txd, 8, word);
					crc32(crc, 0, poly);
					crc = ~crc;
		#pragma xta endpoint "mii_tx_crc_1"
					p_mii_txd <: crc;
					break;
				case 2:
					word = txbuf[idx];
		#pragma xta endpoint "mii_tx_final_partword_2"
					partout(p_mii_txd, 16, word);
					word = crc8shr(crc, word, poly);
					crc8shr(crc, word, poly);
					crc32(crc, 0, poly);
					crc = ~crc;
		#pragma xta endpoint "mii_tx_crc_2"
					p_mii_txd <: crc;
					break;
				case 3:
					word = txbuf[idx];
		#pragma xta endpoint "mii_tx_final_partword_3"
					partout(p_mii_txd, 24, word);
					word = crc8shr(crc, word, poly);
					word = crc8shr(crc, word, poly);
					crc8shr(crc, word, poly);
					crc32(crc, 0, poly);
					crc = ~crc;
		#pragma xta endpoint "mii_tx_crc_3"
					p_mii_txd <: crc;
					break;
			}
	}
}

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