Path: csiph.com!eternal-september.org!feeder.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail From: D Finnigan Newsgroups: comp.sys.apple2.programmer Subject: Uthernet and half-duplex/full-duplex negotiation Date: Sat, 11 Jun 2016 16:04:20 -0000 (UTC) Organization: Mac GUI Lines: 32 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Sat, 11 Jun 2016 16:04:20 -0000 (UTC) Injection-Info: mx02.eternal-september.org; posting-host="ac9e0e4d7dd3957fb97803ee6801bab8"; logging-data="18820"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19uMsdi8xOQ4R0vWr3QL/Kw" User-Agent: Mac GUI Usenet Cancel-Lock: sha1:SRp4WD8xvhi/ajO+uDKQrtXxD+I= Xref: csiph.com comp.sys.apple2.programmer:2782 Dear all, I'm once again improving and testing the Marina IP stack for a June 2016 edition. I've set up two Apple II computers which are connected with a straight-through Ethernet cable. One is running the original Uthernet, the other has the new Uthernet II. I notice that the Uthernet II does not enter into full-duplex mode, and further more, that it seems to receive its own transmissions. Or at least there is some hang-up which causes Marina to get stuck in the ARP Address Conflict Detection Probe loop until I pull the cable and finally it settles into normal operation. This infinite loop does not seem to happen on the Uthernet machine, but it ends up receiving the flood of ARP probes. This problem also does not happen at all when both machines are running an Uthernet II. Both cards enter into 100 Mb/s, full duplex mode. I've checked the manufacturer's documentation for both cards and it's not very clear on how to change from full to half-duplex. Indeed, the W5100 manual includes basically no documentation on full vs half duplex. Has anyone run into this problem and can provide a solution or something to check for in my code? Or maybe I just need to use an actual cross-over cable? I don't think I have one with me at the moment, otherwise I would have tried it before posting here. -- ]DF$ The Marina IP stack for Apple II-- http://marina.a2hq.com/