Hi Eric, Danilo, David and all, I read with interest. First, could we start noting 90% of us hams have a multi-mode HF-VHF transceiver with CAT control.
Or, at the very least the standard DIN audio in/out and PTT connector. Am I special here? I have three Yaesu radios: FT-840, FT-897D and an FT-857. The oldest being fifteen+ years old now. All can be connected to a computer for digital modes. What I think is a worthwhile project is, a small box ala the SM1000 but with a RPi 3B (or similar) and a small touch screen as used in those cheap VNAs. On the box, a mic socket and speaker socket and power socket for 12V. In the radio room here, a standalone unit freeing up my PC, in the field, portable enough. The RTL-SDR may be a useful receiver, but a good clean transmitter is also required. Alan VK2ZIW On Wed, 3 Feb 2021 06:04:34 +1030, David Rowe wrote > Hi Danilo, > I think Eric's proposal was just to swap out the codec, andperhaps using the > existing modem on the radio? > > The current FreeDV modes we have ported to the stm32 (1600 and700D) are aimed > at HF channels, and the GD77 probably doesn't havethe RF hardware to support > them (e.g. a SSB style radio deck). FreeDV includes the modem, protocol, FEC, > and Codec 2 - which maybe overkill for this project. > > I can't recall the exact CPU/memory breakdown between Codec 2 andthe other > parts of the FreeDV stack, but I imagine Codec 2 alonewould require > substantially less resources. > While a GD77 port would be cool, I lean towards full ground upopen source > radio designs like M17 although I'd like to use bettermodems :-) At some > point I'm going to try my open vhf/uhfPI+RTLSDR based radio project with > voice - it's already runningthe FreeDV stack and has plenty of CPU. > > Cheers, > David > > On 3/2/21 4:37 am, Danilo Beuche wrote: > > Hi, > I'd like to share my thoughts on this, as I also have some GD77and love the > OpenGD77 FW (main reason for getting these). I havesome experience with > porting FreeDV to the STM32 arm processoras I was one of the developers who > integrated Codec2 into theUHSDR Firmware a couple of years ago. > > The hardware in the OpenGD77 GD77 is surely not powerful enoughfor 700D, it > may be possible to get it to work with 1600D.FreeDV also eats a big slice of > your RAM (~64k at least) ofwhich the GD77's MK22FN512VLL12R has only 128k. > 120 Mhzis also less than the 168Mhz of the SM1000 or the MCHF with > anSTM32F4xx processor. As both processor belong to the CORTEX-M4family, they > should have similar performance per MHZ. > > In measurements for 1600D on the MCHF with the UHSDRsoftware, this takes > roughly 70% load in the signal processingpath from 48khz IQ to audio for > 1600D. Doing the math 168/120* 70% load = 98% load. 2% cycles left. SSB > decoding takesabout 10%, the remaining 60% went to FreeDV. Not a problem > inSM1600 as it does less signal processing and doesn't have torun a graphical > UI in addition (which the MCHF does). > > 700D runs ok on the STM32F7 processor with 216 Mhz andprocessor caches > (CORTEX-M7 design), speeding up codeexecution quite significantly. The > STM32H7 with 480 Mhz is notconcerned about decoding 700D at all, there is > plenty of cpupower left. But those are unfortunately not in thosehandhelds. > > But for a different FreeDV mode better suited for VHF/UHFusage or a different > signal processing chain it might be anentirely different story. Thats is > where I have to hand overto David and the other experts. > And just for the record: I would love to have a "completely"open source GD77 > with digital voice. > > Danilo > > > > > Can't say anything about the DM1801 > > On 02/02/2021 18:21, Daniel Mundallwrote: > > Hi Eric, > Funny that you mention OpenGD77 as last month Idiscovered these radios > (Baofeng DM-1801 in my case) andpicked up two of them off of aliexpress with > codec2 beingthe primary reason for my purchase. > There are 4 reasons why I think they would be great fitfor codec2: > * They're cheap ($65-75) & available which means youcould get a larger adoption. * They run on an ARM platform either STM32 orsimilar processor. * And there's already an open source firmware withoutinventing that. * The audio encoding isn't a separate chip (at least onthe DM1801) it's software encoding. > Interestingly enough original portion of the memorycontaining the software > audio codec is retained inOpenGD77 to avoid patent issues. > > Another cool possibility that I haven't felt out yetbut in theory because of > the two slot TDMA setup I thinkeither a repeater mode or full duplex audio > should bepossible. > > Anyway, I just got the radios so soon as I have achance I'm going to get > OpenGD77 loaded up and playaround with it. > > One thing that David or the others might be bettersuited to answer is how > much hardware functions of theSTM32 have been used in the codec2 port. > Because therecould be hardware limitations with what is even availableas far > a hardware functions on the MCU. > > Regards, > > Daniel Mundall VA7DRM > > On Tue, Feb 2, 2021 at 5:59AM Eric Jacksch <e...@jacksch.com> wrote: > I don't know enough aboutCODECS to know the right answer (thus must > post here), but right now the OpenGD77 source basicallyincludes an > bit of assembly language to call some binary code lifted outof the > vendor's original firmware. My interest is to drop in adifferent > CODEC, but I don't know enough about them to understandexactly what > needs to be done. > > On Tue, 2 Feb 2021 at 02:48, Mooneer Salem <moon...@gmail.com> wrote: > > > > I'm thinking M17 (based on Codec2) might be better toincorporate since it's > > already building in routing typefeatures that DMR, D-STAR, etc. already > > have. I'm not reallyfamiliar with OpenGD77 but it seems like a neat > > project.Unfortunately I don't have a compatible HT (I use a MD-380for DMR) > > but perhaps it'll gain more support in the future. > > > > -Mooneer K6AQ > > > > On Mon, Feb 1, 2021 at 3:21 PM Eric Jacksch <e...@jacksch.com> wrote: > >> > >> Greetings, > >> > >> Has anyone looked at dropping Codec2 into OpenGD77? > >> > >> In case anyone is not aware, OpenGD77 is a (mostly)open source > >> firmware replacement for several low cost handheldtwo-way radios, > >> including the GD-77 (aka TYT MD-760). > >> > >> To work around intellectual property issues, thefirmware currently > >> links in the DMR CODEC from the original vendor'sbinary. > >> > >> While it would break compatibility with other DMRradios, I'm > >> interested in seeing a fork of OpenGD77 that isfully open source and > >> Codec 2 seems like an obvious candidate. A trulyopen-source amateur > >> VHF/UHF digital mode. > >> > >> The IDE (MCUExpresso) and complete toolchain forOpenGD77 is free and > >> relatively straightforward on Windows, and thefirmware is written in > >> C. What's needed is the Codec 2 expertise. > >> > >> Anyone interested? > >> > >> Cheers, > >> Eric > >> > >> > >> _______________________________________________ > >> Freetel-codec2 mailing list > >> Freetel-codec2@lists.sourceforge.net > >> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > > > > _______________________________________________ > > Freetel-codec2 mailing list > > Freetel-codec2@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > > -- > Eric Jacksch, CPP, CISM, CISSP > e...@jacksch.com > Twitter: @EricJacksch > https://SecurityShelf.com > > _______________________________________________ > Freetel-codec2 mailing list > Freetel-codec2@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > > > _______________________________________________ Freetel-codec2 mailing list Freetel-codec2@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > > _______________________________________________ Freetel-codec2 mailing list Freetel-codec2@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freetel-codec2 --------------------------------------------------- Alan VK2ZIW Before the Big Bang, God, Sela. 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