USB may be a common interface to a computer but practically useless to another microcontroller.
Everything can do serial but not everything can do USB master. In the worst case, use a Serial-USB adapter on your PC. There is no such thing as a Serial-USB master interface and never will there be one. USB is PC centric. Didier KO4BB On June 26, 2014 2:13:00 AM CDT, Chris Albertson <albertson.ch...@gmail.com> wrote: >If you want a common interface for GPS receivers it's "NMEA" and it's >relatively easy to implement. I certain would NOT translate to TSIP as >that is rather obscure. NMEA is a very common standard and many GPSes >can >output NMEA. > >Also you talked about "serial". I hate to say it but "who in 2014 >wants a >serial device? USB is the only reasonable interface to a computer. If >you >used serial then you would just need to buy a serial to USB adapter so >you >may as well build that into your controller. In 2014 those old DB9 >and >DB25 connectors should be banned from all new designs. > >Realistically the user interface in most home made gear is a few >"#ifdef" >in the code at the top of the file. You change those and recompile and >send the new software to the controller. It's not bad having to >re-compile >in order to support a different GPS receiver. You would not want to >swap >the brand of GPS in a user interface. You do that with solder and >wires >and recompiling > > >On Wed, Jun 25, 2014 at 8:14 PM, Bob Stewart <b...@evoria.net> wrote: > >> After reading Chris's response, it dawned on me that I'm treading a >> different path from what I've seen on the list. It's not so much a >GPSDO >> as a general purpose GPSDO engine. It uses a number of ideas from >Bert's >> board, like the dual-rail op-amp output, but it also has a TIC, so it >will >> have sawtooth correction. I have included 2 TTY ports: one for the >> receiver and one for the PC interface. I'm going to use the DAC on >the >> dsPIC, but there will be an SPI port that can be used to drive an >off-board >> DAC, instead. There's also the possibility of switching some stuff >around >> and having an I2C port, and the ICSP header could also hook up to an >> additional thermistor or two, or perform other digital functions. >> >> >> So, there will be some minor user fiddling, like with Bert's board, >due to >> the flexibility of the OCXO. But, I'll be using the P and D from the >PID >> control system, so it shouldn't be difficult to setup. There will be >a >> power LED, an output enable LED, and a bi-color LED to signify >status, but >> only the status would be necessary. I'll do what I can to make it >smart >> enough to plug and play for most circumstances, but I only have the >one >> OCXO brand to test with at the moment. I do have 3 receivers to test >with >> now: Adafruit, UT+, and LEA-6T. Keep in mind that I don't expect >this to >> be a lucrative commercial business venture, so my budget is almost >> nonexistent. >> >> >> I'll look into both SCPI and TSIP, and therein lies the reason for my >> original post. Essentially, have they been patented, and if so, have >those >> patents expired? Some companies guard their interfaces very >rigorously to >> forestall competitive disruption. I don't want to suddenly get a >cease and >> desist letter or a notice of lawsuit over a hobbyist kit. It's one >thing >> to provide open source software to monitor/control a successful >product. >> It's an entirely different thing to provide an alternative product >with an >> identical user interface. >> >> I just ordered the first prototype boards today, but the software >should >> be just a rewrite of what I did for the TIC on Bert's board, with a >lot of >> extras thrown in. Not that that doesn't mean a lot of work, of >course. >> >> >> Bob >> >> >> >> ________________________________ >> From: Tom Van Baak <t...@leapsecond.com> >> To: Discussion of precise time and frequency measurement < >> time-nuts@febo.com> >> Sent: Wednesday, June 25, 2014 9:02 PM >> Subject: Re: [time-nuts] GPSDO standard interface? >> >> >> Bob, >> >> A couple of different ideas: >> >> 1) No UI at all. The surplus GPSDO favorites over the years (like the >HP >> SmartClock's and Trimble Thunderbolt) work with no UI. Yes, there is >a PC >> program you can use to monitor and control it, or even debug it, but >it is >> completely optional. Many GPSDO work out of the box. Maybe, like HP, >have >> one green LED to say all-is-well. >> >> 2) A very simple 9600 baud command set that you can use with any >terminal >> program. Adding LCD is fine too. But make sure everything on the LCD >is >> also available over RS232. Not everyone wants to visually monitor the >LCD >> of every piece of gear on their bench; let a PC log and archive all >the >> data, check for problems, make plots, etc. >> >> 3) Mimic enough of HP's SCPI command set so that GPScon and other >tools >> like that can be used, transparently. I forget if your GPSDO includes >a >> receiver or not. >> >> 4) Mimic enough of Trimble's TSIP so that LH and other tools like >that can >> be used, transparently. >> >> Please write enough code so that the GPSDO, by default, can work "out >of >> the box". I'm evaluating a prototype GPSDO right now that requires >all >> sorts of user input just to get it started and to keep it going. That >gets >> old. My bias is: time spent creating clever adaptive algorithms to >make a >> human unnecessary is better than time spent creating an elaborate UI >that >> requires a user (and operation manual) and constant monitoring or >adjusting. >> >> /tvb >> >> >> ----- Original Message ----- >> From: "Bob Stewart" <b...@evoria.net> >> To: "Discussion of precise time and frequency measurement" < >> time-nuts@febo.com> >> Sent: Wednesday, June 25, 2014 5:10 PM >> Subject: [time-nuts] GPSDO standard interface? >> >> >> In an offline communication, I suddenly realized that I hadn't given >any >> thought to the user interface for my GPSDO. Is there an accepted >standard >> interface for GPSDOs, or is that a murky Microsoft-esque world of >patents >> and lawyers? >> >> >> Bob - AE6RV >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > >-- > >Chris Albertson >Redondo Beach, California >_______________________________________________ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. -- Sent from my Motorola Droid Razr HD 4G LTE wireless tracker while I do other things. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.