From: Andrew Cottrell Newsgroups: comp.os.msdos.djgpp Subject: Re: Libnet serial port problem Date: Tue, 14 Jan 2003 18:02:48 +1100 Organization: ECLiPSE Lines: 42 Message-ID: References: NNTP-Posting-Host: p150-tnt6.syd.ihug.com.au Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: lust.ihug.co.nz 1042527774 9167 203.173.146.150 (14 Jan 2003 07:02:54 GMT) X-Complaints-To: abuse AT ihug DOT co DOT nz NNTP-Posting-Date: Tue, 14 Jan 2003 07:02:54 +0000 (UTC) X-Newsreader: Forte Agent 1.92/32.572 To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Reply-To: djgpp AT delorie DOT com >I'm having some trouble with some serial port code I'm writing with >Libnet under djgpp. Everything's fine if I only use one serial port, >but if I try to receive from both serial ports at once, information >can only get through from one of them at a time. Each serial port >works fine by itself. ...SNIP... What is Libnet? I have not heard of it before. >So, my questions are: is this a hardware limitation? Is it a limitation >in Libnet's serial driver, or in Libnet generally? Am I doing something >wrong? Is there a workaround? Will this problem also apply to Libnet's >IPX or IP drivers? (I don't have access to a LAN or to the 'net from my >development computer, so I can't test these) > >This is quite a specific question, so I'm not sure anyone will be >able to shed light on it. But any help would be much appreciated. Serial ports can share interrupts and as long as the serial library can handle this then you won't see any problems. Sharing of interrupts is a hardware configuration. With regards to UARTS if you are runnign at 56K or Higher then you will need to use a 16550 or higher UART and enable the FIFO. If you are not using a serial library that supports the FIFO then forget about high speed serial data. There are a few comms libraries allready theat work under DJGPP and support mutliple comm ports at the same time, the two that I have used are DZCOMM and PMCOM. In general up until the beginning of december I would have recommended PMCOM, but I have found some motherboards with an ALI based chipset where PMCOM does not work, but DZCOM does not have support for some of the RS232 signals which PMCOM does. To see if there has been anyone else on the list mention Libnet goto www.delorie.com and have a look at the mail archives and do a search, but I can't remember ever seeing any in the last 5 years. When you get to the low level hardware drivers the UART & Ethernet are completly differenct and the Libnet support would probably reply on a driver that was supplied by the network card manufacturer so it should be okay. This assumes that the Libnet has this sort of support in it. Andrew