Wow, a long thread, Thanks for the inputs, I am following up on the links. It looks like there is no clear cut winner in getting, say half a dozen machines linked using RS485, a simple master-slave polling scheme, where machines queue up outgoing requests and only speak when spoken to would be simplest. The other candidates seem onerous. The real trick will be to provide a physical layer that can link to a standard TCP protocol stack. When I get my linux board I'll start dismantling some of the ethernet drivers, maybe I can "fool" the TCP/IP stack to think it is connected to a perfect (unbusy) network. I'll revisit slip and ppp then. Thanks again Ian McCrum MI5AFL. ( actually I just realised AX25 might be a good candidate as well...) University of Ulster
RS485, multidrop protocol
Started by ●November 14, 2004
Reply by ●November 16, 20042004-11-16
Reply by ●November 17, 20042004-11-17
Ian McCrum MI5AFL wrote:> Wow, a long thread, Thanks for the inputs, I am following up on the > links. > > It looks like there is no clear cut winner in getting, say half a > dozen machines linked using RS485, a simple master-slave polling > scheme, where machines queue up outgoing requests and only speak when > spoken to would be simplest. The other candidates seem onerous. > >> Thanks again > Ian McCrum MI5AFL. > ( actually I just realised AX25 might be a good candidate as well...) > University of Ulsterwww.micrium.com offers an inexpensive ModBus package. Scott
Reply by ●November 30, 20042004-11-30
Ted Wood schrieb:> Ian McCrum MI5AFL <IJ.McCrum@ulster.ac.uk> wrote in message news:<67gfp0dr2na07h75ic7i939d15r2pelcf5@4ax.com>... > > try:---8<---- http://www.p-net.dk cheers Gunther