Sub string match.
'[PIC]:[EE]: ARP, ICMP, UDP/IP on a 16F877 using 3C'
|Circuit pics & application screen shot:
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 :)
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]: PIC only [EE]: engineering [OT]: off topic [AD]: advertisements
M. Adam Davis
More... (looser matching)
- Last day of these posts
- In 2000
, 2001 only
- New search...