jdownj 1 Posted February 1, 2012 Share Posted February 1, 2012 I am banging something together to provide a hardware solution to a service problem. Due to unreliable connections, my cable modem drops offline every 24-36 hours, requiring a reboot. I want to build a device that will: -Connect via Ethernet. -Ping a known server every 5 mins. -If server is unreachable, pulse an output high, resetting the cable modem. I am thinking G2553/Wiznet 5100, but if anyone has any ideas on how to lower the BOM cost or explanations on why I need to reconsider that, please let me know. Currently I implement this functionality on my router(OpenWRT), but it is possible for the router to freeze as well. I think a hardware watchdog like this is the most reliable solution. Quote Link to post Share on other sites
bluehash 1,581 Posted February 1, 2012 Share Posted February 1, 2012 Did you know about this? Quote Link to post Share on other sites
RobG 1,892 Posted February 1, 2012 Share Posted February 1, 2012 I think Wiznet is the best way to go, but as you already know, modules are kind of pricey, ~$20 + s/h. Maybe we could start a project here to design a W5x00 based board (reverse engineering is another option.) Wiz chips are ~$3-$5, other parts <$5, I think we could build a web server board for under $10. BTW, I need one for my home automation project. Quote Link to post Share on other sites
bluehash 1,581 Posted February 1, 2012 Share Posted February 1, 2012 Well.. I'm all for a BP or a board. Quote Link to post Share on other sites
gordon 229 Posted February 1, 2012 Share Posted February 1, 2012 Well, your router should have a hardware watchdog already (if not, time to get something made in this millenium ) and at the very least some unused GPIO ports as well. In this particular case, unless you have some other prohibiting factors (distance between cable modem and router or whatnot), I think building a separate device is the least practical thing to do (not counting the fun factor, of course ). Quote Link to post Share on other sites
jdownj 1 Posted February 1, 2012 Author Share Posted February 1, 2012 I have been following the wifi booster project. I don't think much from that will apply, except for code. I am shooting for a total BOM less than that wifi module. I am not a coder, but I'm doing my best to learn. My plan for this board is: MCU/Ethernet Chip 802.3af PoE 2-3 GPIOs with transistor to drive relay. Other GPIOS available on header. I am aiming for a total BOM less than $20. If others are interested, I am certainly open to making kits or selling bare boards. Fair warning, SMD doesn't scare me;). Wiz5100 is 80-LQFP, and I will likely go QFN on the MCU. Most PoE chips are also "effing tiny". Board space is expensive... I hope to beat both the size and BOM cost of the Dangerous Prototypes Web Platform, about the closest available device. Quote Link to post Share on other sites
jdownj 1 Posted February 1, 2012 Author Share Posted February 1, 2012 @gordon, I currently implement that on my router, but my issue is that my router runs many services, and some have their own reasons for locking up. OpenWRT is stable... CUPS/Samba/Asterisk not so much... Because I am away from home often, and I access stuff on my network via VPN, I am really chasing brute reliability here. It is annoying to have to wait for an acceptable hour to call the neighbor to reboot the router/modem. Quote Link to post Share on other sites
gordon 229 Posted February 1, 2012 Share Posted February 1, 2012 In that case... exactly what this was designed for... . Quote Link to post Share on other sites
cde 334 Posted February 1, 2012 Share Posted February 1, 2012 @gordon,I currently implement that on my router, but my issue is that my router runs many services, and some have their own reasons for locking up. OpenWRT is stable... CUPS/Samba/Asterisk not so much... Because I am away from home often, and I access stuff on my network via VPN, I am really chasing brute reliability here. It is annoying to have to wait for an acceptable hour to call the neighbor to reboot the router/modem. Turn a msp430 into a watchdog, combined with a script on the openwrt router. Router script pings server, if good, toggles gpio. This triggers an interrupt on the msp430, which resets its countdown timer. 3 missed resets, it reboots the router. No need for a ethernet/wifi connection on the msp430's part, and allows for it to be small and internal to the router, and powered from it too. Minimal coding required. Alternatively, instead of just a gpio, you can use one of the serial ports on the router instead. Quote Link to post Share on other sites
jdownj 1 Posted February 1, 2012 Author Share Posted February 1, 2012 Thanks! Damn I hate it when a perfectly good project is shot down by superior thinking;) I may continue the idea of an Ethernet dev board, but you guys have definitely provided a better solution to the problem at hand. Quote Link to post Share on other sites
Rei Vilo 695 Posted November 7, 2017 Share Posted November 7, 2017 The G2553 has only 512 bytes of RAM. Go for a LaunchPad which MCU has more RAM. bluehash 1 Quote Link to post Share on other sites
Rickta59 589 Posted November 7, 2017 Share Posted November 7, 2017 nothing like a timely response bluehash 1 Quote Link to post Share on other sites
veryalive 49 Posted November 8, 2017 Share Posted November 8, 2017 Like the old saying goes" "Better never than late".... or was that the other way around ?!? Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.