Hi Georg, Thank you for your suggestion. However, we once checked the EMAC0_MR1, and it was right configuration. Sorry, not to be informed to you. But I'll check once again. As a fact, this problem does not happen everywhere. We need to go another place and it's far from here. Therefore, next investigation will be held at the middle of next week. I will keep you informed as more information becomes available.
Regards, Kishinami --- On Fri, 28 Feb 2003 22:59:11 +0900 Georg Klug<gklug at giga-stream.de> -san wrote: >> We are debugging a custom board designed based on the 405GP >> (200MHz) and have a problem not being sent ECHO REPLY ping >> packet from custom board to our PC via repeater hub on the >> heavy traffic under 10Mbps and half duplex condition. > >> ... > >> Following are the our simplest duplication process and the >> results. >> >> 1. Connect the repeater hub to backbone LAN. >> 2. Connect custom board, test PC to ping and other PCs to the >> repeater hub to the full. This case, 10 or more PCs are >> connected to repeater hub and each PC works normally by >> using network. >> 3. Increase the traffic by using ftp command. The ftp data was >> never addressed to the custom board. >> 4. Ping from our PC to custom board at one time. >> 5. The 60% pings were lost such condition. >> 6. We investigated the ping lost case. >> - LAN protocol analyzer captured the ECHO REQUEST which was >> address to custom board. It shows ECHO REQUEST was issued >> from our PC to LAN cable. >> - Logic analyzer captured the same ping packet which was >> already been captured by LAN analyzer between PHY(Intel >> LXT971A) and EMAC. It shows ECHO REQUEST was reached just >> before the EMAC. >> - The LAN device driver's receive buffer did not receive the >> ECHO REQUEST by using printk command. We suspected that the >> ECHO REQUEST was not issued to the MAL(Memory Access Layer), >> therefore ECHO REQUEST was not translated to the receive >> buffer. >> >> At the same time, many 4 byte short packet(0x000000f0) which was >> not addressed to custom board was received to the LAN device driver's >> receive buffer with error status. According to 405GP manual, EMAC >> discards the packet which is not of its own. > >to me it looks like an half duplex issue. You should check whether both: >sender and receiver know that they are connected to a half duplex hub. >Otherwise collisions could occur which are not detected by the receiver >and also not by the transmitting entity. So you should make sure that >FDE is set to 0 in the EMAC Mode register 1 (EMAC0_MR1) according to >the Users manual) > ----- KISHINAMI Masaya Fujitsu Limited (Japan) ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
