October 2022 - pacsat - mailman.amsat.org

Prototype Code
by Chris Thompson 26 Oct '22

26 Oct '22

I mentioned to Jim and some others that I was working on some Pacsat code for an ARISS project. This is just a prototype but it may be useful, especially for those seeking to understand the protocols. I cleaned up the code a bit and checked it all in to here: https://github.com/ac2cz/Pacsat/ I leveraged some of the old 1990s code from programs like PG and PB, but they are written in an old style of C that modern gcc does not like. They also rely on the bit size of char, int and long (and time_t it seems) in a way that does not work with modern computers. So I updated much of that to use uint32_t etc. Also PB/PG are for a ground station whereas this code is for the server. So there were just a few structures and routines to leverage, but most of this is new code. This runs on Linux and has been tested on Ubuntu and the Raspberry PI. I have assumed a little endian machine, there is no code to cope with big endianess It works with Direwolf's AGW engine as the TNC. I picked that over the KISS interface so I do not have to implement the connected mode state machine for AX25. Right now this just implements the broadcast protocol. Specifically it stores the PB status for up to 10 stations, it transmits the PB status periodically, handles directory broadcast requests and file broadcast requests. The functionality to handle holes in the directory and files is not fully tested, but the broadcast of a new directory or of a new file seem to work well. I have no idea how these things were done in previous spacecraft, so I chose a linked list for the directory, which is rebuilt at startup, and a fixed structure to hold 10 stations on the PB, with memory allocated and freed for the list of holes that they supply. If the directory grows to a large size then a hash table index by file id may be useful to save CPU at the expense of memory, but it is probably not needed given the frequency of requests is likely low (per second). The code it split into files to handle the creation or parsing of Pacsat Headers and Files, the creation and maintenance of a directory and the broadcast protocol. There are also test routines for each file, which you can see at the end. These demonstrate how most of the functions work. The Pacsat header/file routines may be the most useful to leverage as they are a pain to write and probably very portable. Though I have assumed a normal C file system to load/save the files. I'm happy to answer questions or discuss with anyone if that is helpful. I don't claim any great skill in the C language, so feel free to point out any issues or make suggestions if you want. Next I am going to finish up the handling of holes and then implement FTL0 for file uploads. I want to setup a test loop to measure the relative performance of AX25 vs FX25 under simulated LEO conditions. I also want to see if this prototype will work for the mission objectives of the ARISS Student Sensor project. 73 Chris -- Chris E. Thompson chrisethompson(a)gmail.com g0kla(a)arrl.net

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Re: PACSAT Components in My Possession
by Chris Thompson 25 Oct '22

25 Oct '22

Assuming you can ship some of the parts to me in Canada then I am willing to help in whatever way I can. Either testing with the ground station I developed, porting some of the Pacsat server code that I have written for ARISS or whatever else helps. Let me know. 73 Chris G0KLA / AC2CZ On Tue, Oct 25, 2022 at 11:30 AM Jonathan Brandenburg via pacsat < pacsat(a)amsat.org> wrote: > > > > ---------- Forwarded message ---------- > From: Jonathan Brandenburg <jbrandenburg(a)amsat.org> > To: pacsat(a)amsat.org > Cc: > Bcc: > Date: Tue, 25 Oct 2022 10:29:55 -0500 > Subject: [pacsat] Re: PACSAT Components in My Possession > On 10/24/2022 4:36 PM, JIm McCullers wrote: > > Is some of each acceptable? > Absolutely! > > I need a couple Launchpad boards to work out the dimensions and header > sizes needed for a daughter board. > > The documentation is sketchy to none. > That makes sense. I figure each active pacsat developer needs at least > one and perhaps two Launchpad boards. > > When do you believe the Raspberry Pi boards will be in? > > I want to do one while working on the Launchpad daughter board. > > If it's soon that would save one shipping. > OSHPark expects the panel on Thursday and will likely ship the boards to > me quickly after receiving the panel. I expect the Raspberry Pi boards > early next week. I'd expect each pacsat developer to need three boards > at peak development to implement a two-up-one-down system. If I'm right, > it might make sense to wait until the Raspberry Pi boards arrive. (For > those that might be confused, the Raspberry Pi boards are a convenient > way to develop using the AX5043 and can be jumpered to the LaunchPad... > I've done that before.) (Also, to be clear, the Raspberry Pi boards > require assembly with surface mount components. In particular the AX5043 > has a ground pad making the use of a reflow oven beneficial. Admittedly > it could be done with hot air and hand-soldering, too.) > > As to the board you sent me, do you have the schematic available? > > I'll assume it's Kicad. Package it together with any support libraries > and send it to me. > > I'll switch to my other computer and pull up what I have. I won't have > any software specifically written for that prototype board I > accidentally sent you as I hadn't assembled one. But I think you'll find > the AX5043 portion to be a lot like the V1.3 board with the addition of > the second antenna connection. Thus, the software written for the V1.3 > board should be functional on the prototype board. > > Jonathan > > -- > Jonathan Brandenburg, KF5IDY > > > > > ---------- Forwarded message ---------- > From: Jonathan Brandenburg via pacsat <pacsat(a)amsat.org> > To: pacsat(a)amsat.org > Cc: > Bcc: > Date: Tue, 25 Oct 2022 10:29:55 -0500 > Subject: [pacsat] Re: PACSAT Components in My Possession > ----------------------------------------------- > pacsat mailing list -- pacsat(a)amsat.org > View archives of this mailing list at > https://mailman.amsat.org/hyperkitty/list/pacsat@amsat.org > To unsubscribe send an email to pacsat-leave(a)amsat.org > Manage all of your AMSAT-NA mailing list preferences at > https://mailman.amsat.org > -- Chris E. Thompson chrisethompson(a)gmail.com g0kla(a)arrl.net

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Re: PACSAT Components in My Possession
by Rich Gopstein 25 Oct '22

25 Oct '22

I believe the license allowed for the code to be ported to another processor if you were talking to an ax5043. The language was ambiguous, but I believe that was the intent. Rich On Tue, Oct 25, 2022 at 12:02 PM Jonathan Brandenburg via pacsat < pacsat(a)amsat.org> wrote: > > > > ---------- Forwarded message ---------- > From: Jonathan Brandenburg <jbrandenburg(a)amsat.org> > To: pacsat(a)amsat.org > Cc: > Bcc: > Date: Tue, 25 Oct 2022 11:02:11 -0500 > Subject: [pacsat] Re: PACSAT Components in My Possession > On 10/25/2022 10:50 AM, JIm McCullers wrote: > > Do you have any files from Ax-RadioLab you used on the original board? > > I've installed the IDE but yet to have time to play with it > > I probably do have the files I originally used to investigate the AX5043 > radio. I believe they're in a virtual machine I just stumbled across > last week. I didn't post those to the repository because I used them > only as a supplement for the documentation and didn't use them to > specifically implement the software in > https://github.com/BrandenburgTech/DigitalTxRxRPi. > > I recall an interesting license restriction when using the output of > Ax-RadioLab... I believe the generated software cannot be ported to > another processor. Thus, I used the output of Ax-RadioLab only as a > supplement to documentation and didn't port the generated software. > > Jonathan > > -- > Jonathan, KF5IDY > > > > > ---------- Forwarded message ---------- > From: Jonathan Brandenburg via pacsat <pacsat(a)amsat.org> > To: pacsat(a)amsat.org > Cc: > Bcc: > Date: Tue, 25 Oct 2022 11:02:11 -0500 > Subject: [pacsat] Re: PACSAT Components in My Possession > ----------------------------------------------- > pacsat mailing list -- pacsat(a)amsat.org > View archives of this mailing list at > https://mailman.amsat.org/hyperkitty/list/pacsat@amsat.org > To unsubscribe send an email to pacsat-leave(a)amsat.org > Manage all of your AMSAT-NA mailing list preferences at > https://mailman.amsat.org >

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Re: PACSAT Components in My Possession
by Jonathan Brandenburg 25 Oct '22

25 Oct '22

On 10/25/2022 10:50 AM, JIm McCullers wrote: > Do you have any files from Ax-RadioLab you used on the original board? > I've installed the IDE but yet to have time to play with it I probably do have the files I originally used to investigate the AX5043 radio. I believe they're in a virtual machine I just stumbled across last week. I didn't post those to the repository because I used them only as a supplement for the documentation and didn't use them to specifically implement the software in https://github.com/BrandenburgTech/DigitalTxRxRPi. I recall an interesting license restriction when using the output of Ax-RadioLab... I believe the generated software cannot be ported to another processor. Thus, I used the output of Ax-RadioLab only as a supplement to documentation and didn't port the generated software. Jonathan -- Jonathan, KF5IDY

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PACSAT Components in My Possession
by Jonathan Brandenburg 25 Oct '22

25 Oct '22

Howdy! I confirmed the package I received this past week was the 10 x Launchpad boards That means I have the following: * 10 x TMS570 Launchpad boards * 250 x AX5043 chips * 2 x Raspberry Pi Radio Board V1.3 stencils Do I need to provide these to anybody local or remote? On the way are still: * 9 x Raspberry Pi Radio Board V1.3 PCBs -- Jonathan, KF5IDY

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AMSAT Symposium?
by Rich Gopstein 21 Oct '22

21 Oct '22

Just curious who else will be attending. I'm flying out later tonight. It would be nice to meet up at some point. Rich, KD2CQ

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Launchpads
by Jonathan Brandenburg (KF5IDY) 20 Oct '22

20 Oct '22

Kari (my wife) tells me 10 Launchpads arrived yesterday. Hooray! I’ve also ordered some AX5043 PCBs and a couple solder stencils. Along with the previously received AX5043 chips that should be getting us well on our way to development environments. Jonathan Sent from my iPhone

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GOLF-ASCENT-FOX+ Eng Coord Session CANX
by Eric Skoog 13 Oct '22

13 Oct '22

As I mentioned at tonight's session, we will NOT hold a meeting next Wednesday as several principal team members will be attending the AMSAT Space Symposium. Consequently, our next Eng Coord Session will be on 26 October. eric (K1TVV)

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Re: Pacsat conops
by Burns Fisher (AMSAT) 11 Oct '22

11 Oct '22

Brilliant. After saying it should be on the pacsat list, I did not put it there. I have now. 73, Burns Fisher, WB1FJ *AMSAT(R) Engineering -- Flight Software* On Sun, Oct 9, 2022 at 5:12 PM Bob Stricklin <bstrick(a)n5brg.com> wrote: > The original PACSAT software was written by Chris Jackson ZL2TPO/G7UPN. > > The open source package was written by Chris Thompson, AC2CZ. I just > downloaded his package on GitHub and noticed he made changes in it 8 days > ago. > > I think people have been working with AC2CZ software on Pacsat. > > Bob > > On Oct 9, 2022, at 2:44 PM, Burns Fisher (AMSAT) <wb1fj(a)fisher.cc> wrote: > > This all needs to be on the PACSAT list, especially so Chris will see it > and so we are openly sharing the info. Unless there is different > FalconSat-3 ground software, Chris wrote it as a variant of FoxTelem, and > it is totally open source. I don't know of any FalconSat-3 software that > we sell, unless that was sometime ago. > 73, > > Burns Fisher, WB1FJ > *AMSAT(R) Engineering -- Flight Software* > > 73, > > Burns Fisher, WB1FJ > *AMSAT(R) Engineering -- Flight Software* > > > On Sun, Oct 9, 2022 at 3:35 PM Bob Stricklin <bstrick(a)n5brg.com> wrote: > >> >> >> Includes some minor changes in wording a spelling change and comments on >> PACSAT protocol. >> >> I have found some of the info on FalconSat on the web but maybe this >> needs more understanding. >> >> Probably will make enough changes in the software of PACSAT that the >> ground station software needs to be different. >> I think early on AMSAT was controlling the ground station software for >> some revenue. Will need to decide if it is open source or still controlled. >> >> Bob >> >> >> > On Oct 9, 2022, at 11:38 AM, Bill <bill(a)brconnect.com> wrote: >> > >> > My project objectives are simple: >> > >> > Phase I - build something simple, using existing and proven bbs >> protocols. Have it available ASAP for the next launch opportunity. >> > >> > Phase II - build it better....... >> > >> > Here is my conops so far. Thanks for helping me author it. Either edit >> this doc and redistribute, or send changes and additions to me and I will >> incorporate them... >> > >> > Lets try and meet using GoToMeeting next Thursday. >> > >> > Thanks for helping me. My skin cancer surgery was simple and provided >> a complete cure, but the follow-on plastic surgery to repair things is >> extensive. >> > ( 2.5 hrs in surgery. 2nd surgery in a few weeks....) >> > >> > Bill >> > >> > >> > <PacsatConOps2.odt> >> >> >

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AX5043 Stock
by Jonathan Brandenburg 10 Oct '22

10 Oct '22

Hello, I received our order of 250 x AX5043 chips today. Jonathan -- Jonathan Brandenburg, KF5IDY

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