Will be travelling on business so will be out of touch next day or two. Regards Paul
On Mon, Apr 21, 2014 at 7:35 PM, Chris Albertson <albertson.ch...@gmail.com>wrote: > I just changed the thread title to "BPSK Processing" > > If you are having problems with the software what you need to do is start > working on it in an easier environment. That would be some IDE like > Eclipse on a standard desktop or notebook computer. You can feed your > software made-up test data from a text file and send output to the screen. > Get this working first them move to the target hardware. If you write > in C there is better chance of (1) getting help and (2) finding a library > to do most of what you want. > > But start here by listing (post to this thread) exactly what you expect to > see as input and what output you'd like to generate. Seeing real numbers > rather then some daulitative description is the first step. > > Post code examples and ask for advice. > > > > > On Mon, Apr 21, 2014 at 1:29 PM, paul swed <paulsw...@gmail.com> wrote: > > > Good afternoon very interested in the work you are doing with the STM > > board. > > As I mentioned far earlier in this thread I am attempting to use it to > > correct the BPSK WWVB signal here. Initial thoughts were using FORTH to > > program the STM board. > > Very curious what you are using as examples. > > My experience in FORTH is from many years ago and have done very poorly > at > > C. But this may be the case to have something of interest to actually do. > > In either language. > > Regards > > Paul > > WB8TSL > > > > > > On Mon, Apr 14, 2014 at 12:27 PM, d0ct0r <t...@patoka.org> wrote: > > > > > > > > > > > I was experimenting with the same setup for STM32 MCU. This > > microprocessor > > > has accept the sine wave from external OCXO or GPSDO. No problem with > > this. > > > The only thing: I was need to start MCU from slow "watch" crystal > first. > > > And then switch it to work to external one. In another case I got > > incorrect > > > timing settings for MCU. Later, I decide to implement LTC6957-3 chip to > > > "share" REFCLOCK source, since that chip has two equal CMOS-level > > outputs. > > > Unfortunately I have no tool to measure the phase noise and jitters on > > > each setup. > > > > > > > > > > > > > > > It turns out all of this is built into the AVR chip. There is a > > counter > > >> and logic to copy the current counter value to a register on a PPS > pulse > > >> raising edge. The counter keeps running and every second its value > is > > >> trapped. > > >> > > >> I can connect the OCXO and the PPS directly to the AVR pin. The AVR > has > > >> hardware (a fast comparator) to "square" a low amplitude sine wave and > > >> trap > > >> the counter on a zero crossing. So it looks like I can get rid of > ALL > > >> of > > >> the external chips. The built in DAC is working well also but it > needs > > >> some external resisters and caps. > > >> > > >> No need for '74 FFs or '373' or counter chips. I do get precision > > >> timing > > >> with no time critical software, no 74xxx chips. > > >> > > > -- > > > WBW, > > > > > > V.P. > > > > > > _______________________________________________ > > > 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. > _______________________________________________ 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.