Post by thread:[PIC]:[EE]: ARP, ICMP, UDP/IP on a 16F877 using 3C

Circuit pics & application screen shot: http://www.rof.net/yp/alphaone/activities/electronics/3c509b/ Works with most any variation of the 3c509b family, but I have only tested on a TP network using TP, TPO, TPC cards. I can 'ping' it, and control/monitor any I/O port on the 16F877 from my program. With no multiplexing, I have 8 A/D inputs, and 5 digital I/O. RC0-1 are also available as digital I/O if a RTC is not required (or if implemented using the 4MHz clock). With a latch/buffer on the board, I could add 14 digital I/O to that mix. TCP & HTTP are possible, but I don't plan on pursuing it yet. I think a custom app has more flexibility and greater potential for user-friendliness, encryption and network-related exception processing than a browser could ever offer in combination with a chip of this (minimal) processing power. The circuit draws 35-40mA at 5VDC with the NIC powered up. Various 'sleep' modes can bring that down considerably (according to the docs - have not tried it). Packet length is limited in this implementation, but a little work could allow somewhere around 300+ bytes of buffer space. The card itself has a 1k RX buffer by default, but is available only as a FIFO. This was done over a period of two weeks spare time as a hobbyist project. I am still contemplating whether to release the source and circuit details - the study of 1800 pages of data sheets and RFCs, combined with a couple weeks of late nights lead me to believe there may some small bit of commercial potential in this gadget, and my '78 FJ40 needs tires :) JB -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]: PIC only [EE]: engineering [OT]: off topic [AD]: advertisements

I didn't know Maxim semiconductor had their own magazine! I'll have to find me one. ;-) -Adam JB wrote: {Quote hidden}> > Circuit pics & application screen shot: > > http://www.rof.net/yp/alphaone/activities/electronics/3c509b/ > > Works with most any variation of the 3c509b family, but I have only tested on a TP network using TP, TPO, TPC cards. I can 'ping' it, and control/monitor any I/O port on the 16F877 from my program. With no multiplexing, I have 8 A/D inputs, and 5 digital I/O. RC0-1 are also available as digital I/O if a RTC is not required (or if implemented using the 4MHz clock). With a latch/buffer on the board, I could add 14 digital I/O to that mix. > > TCP & HTTP are possible, but I don't plan on pursuing it yet. I think a custom app has more flexibility and greater potential for user-friendliness, encryption and network-related exception processing than a browser could ever offer in combination with a chip of this (minimal) processing power. > > The circuit draws 35-40mA at 5VDC with the NIC powered up. Various 'sleep' modes can bring that down considerably (according to the docs - have not tried it). > > Packet length is limited in this implementation, but a little work could allow somewhere around 300+ bytes of buffer space. The card itself has a 1k RX buffer by default, but is available only as a FIFO. > > This was done over a period of two weeks spare time as a hobbyist project. I am still contemplating whether to release the source and circuit details - the study of 1800 pages of data sheets and RFCs, combined with a couple weeks of late nights lead me to believe there may some small bit of commercial potential in this gadget, and my '78 FJ40 needs tires :) > > JB > > -- > http://www.piclist.com hint: PICList Posts must start with ONE topic: > [PIC]: PIC only [EE]: engineering [OT]: off topic [AD]: advertisements -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics