April 2023 - pacsat-dev - mailman.amsat.org

Re: PC-104 "Standard"
by Burns Fisher (AMSAT) 07 Apr '23

07 Apr '23

I'd be interested if those who use PC104 actually use them throughout the satellite (i.e. they use them like Fox/Golf uses the QxN connectors where most of the signals pass through). Also what board spacing where these connectors are used if there is anything typical. (I think Eric said there were choices for the PC-104 connectors). 73, Burns Fisher, WB1FJ *AMSAT(R) Engineering -- Flight Software* On Fri, Apr 7, 2023 at 10:26 AM Jonathan Brandenburg via pacsat-dev < pacsat-dev(a)amsat.org> wrote: > Following up on last night's conversation... > > When there is talk about CubeSats using the PC-104 standard, what that > really means is the use of the PC-104 form factor in terms of board > size, mounting hole placement, and the 2x2x26 connector. CubeSats don't > adhere to any of the signalling or protocol aspects of PC-104 standards > (including additional connectors defined in the PC-104 standard). > > There hasn't been any standards body define this form factor for > Cubesats (as far as I know) so I imagine it just sort of grew > organically from the first university satellites looking around for > something to copy and noticed the small form-factor computer. > > As correctly noted, CubeSats don't standardize the use of the pins in > the PC-104 connector but it seems like component manufacturers looked > around to see how others had been using pins and followed suit. Thus if > PACSAT is using I2C, power, and ground pins there will be little > conflict. What I've seen is CubeSat component manufacturers offer an > option sheet that allows the customer to select from a set of options. > Along the lines of "put I2C pins here or there or do not connect" kind > of options. > > I hear the comments about how "This a large connector!" and "How many > pins are really needed?" and "How are they used by different > components?" All that is true. At same time it's also true that if > somebody is adding a component to their CubeSat it will most likely > expecting boards with the PC-104 form factor. AMSAT is an exception but > even then we had to partially adapt our boards to the PC-104 form factor > for use by non-AMSAT organizations. > > When I'm at CubeSat Developers Workshop later this month, I'll do a > survey. While I will see at least one university eschew the PC-104 form > factor (because they're developing ALL the components in-house and > prefer a plug-in-slot configuration because it simplifies assembly a > lot) I expect most will have purchased the bus (including structure, > C&DH, EPS, and any ADCS) which will be in the PC-104 form factor. But I > could be surprised and the tide may be turning. > > Comments? > > Jonathan > > -- > Jonathan Brandenburg, KF5IDY > > > ----------------------------------------------------------- > > pacsat-dev mailing list -- pacsat-dev(a)amsat.org > View archives of this mailing list at > https://mailman.amsat.org/hyperkitty/list/[email protected] > To unsubscribe send an email to pacsat-dev-leave(a)amsat.org > Manage all of your AMSAT-NA mailing list preferences at > https://mailman.amsat.org >

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PC-104 "Standard"
by Jonathan Brandenburg 07 Apr '23

07 Apr '23

Following up on last night's conversation... When there is talk about CubeSats using the PC-104 standard, what that really means is the use of the PC-104 form factor in terms of board size, mounting hole placement, and the 2x2x26 connector. CubeSats don't adhere to any of the signalling or protocol aspects of PC-104 standards (including additional connectors defined in the PC-104 standard). There hasn't been any standards body define this form factor for Cubesats (as far as I know) so I imagine it just sort of grew organically from the first university satellites looking around for something to copy and noticed the small form-factor computer. As correctly noted, CubeSats don't standardize the use of the pins in the PC-104 connector but it seems like component manufacturers looked around to see how others had been using pins and followed suit. Thus if PACSAT is using I2C, power, and ground pins there will be little conflict. What I've seen is CubeSat component manufacturers offer an option sheet that allows the customer to select from a set of options. Along the lines of "put I2C pins here or there or do not connect" kind of options. I hear the comments about how "This a large connector!" and "How many pins are really needed?" and "How are they used by different components?" All that is true. At same time it's also true that if somebody is adding a component to their CubeSat it will most likely expecting boards with the PC-104 form factor. AMSAT is an exception but even then we had to partially adapt our boards to the PC-104 form factor for use by non-AMSAT organizations. When I'm at CubeSat Developers Workshop later this month, I'll do a survey. While I will see at least one university eschew the PC-104 form factor (because they're developing ALL the components in-house and prefer a plug-in-slot configuration because it simplifies assembly a lot) I expect most will have purchased the bus (including structure, C&DH, EPS, and any ADCS) which will be in the PC-104 form factor. But I could be surprised and the tide may be turning. Comments? Jonathan -- Jonathan Brandenburg, KF5IDY

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Filesystem interface to mram
by Corey Minyard 07 Apr '23

07 Apr '23

Here's the email I sent earlier. You can ignore the questions about MRAM. I have integrated the Reliance Edge filesystem into the PacSatSw repository in the "filesystem" branch. However, it is still missing the lower level interface to the mram devices. The main filesystem interface is in reliance-edge/include/redposix.h, I have enabled POSIX support without rename. It's pretty straightforward. You can get a copy of the Reliance Edge development document from https://www.tuxera.com/resources/reliance-edge-developers-guide/, but I don't think you need it. I have a copy, and I don't see that I can't redistribute it, so maybe I'll add it to the repository. Are we using the mram code in the deviceSupport directory? If so, the read and write operations (readMRAMWord, writeMRAMWord) don't have prototypes in the header. But I can fix that and integrate. Jonathan, I guess I'll need a launchpad and a board with the mram, since the qemu stuff didn't work out. -corey

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Mail delivery
by Bill 07 Apr '23

07 Apr '23

Corey, please try again...

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test from bf
by Burns Fisher (AMSAT) 07 Apr '23

07 Apr '23

test 73, Burns Fisher, WB1FJ *AMSAT(R) Engineering -- Flight Software*

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Test
by Corey Minyard 07 Apr '23

07 Apr '23

Test is the mailing list is working. -corey

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Re: Pacsat dev mtg 4/6/2023
by Jonathan Brandenburg 06 Apr '23

06 Apr '23

I'll likely be on the road back from Houston but will strive to dial in to listen. Jonathan On 4/6/23 10:37, Bill via pacsat-dev wrote: > > Thu, Apr 6, 2023 7:00 PM - 9:00 PM (CDT) > > Please join my meeting from your computer, tablet or smartphone. > > https://meet.goto.com/325976013 > > You can also dial in using your phone. > (For supported devices, tap a one-touch number below to join instantly.) > > United States: +1 (571) 317-3122 > - One-touch: tel:+15713173122,,325976013# > > Access Code: 325-976-013 > > > Get the app now and be ready when your first meeting starts: > https://meet.goto.com/install > > > > ----------------------------------------------------------- > > pacsat-dev mailing list -- pacsat-dev(a)amsat.org > View archives of this mailing list at > https://mailman.amsat.org/hyperkitty/list/[email protected] > To unsubscribe send an email to pacsat-dev-leave(a)amsat.org > Manage all of your AMSAT-NA mailing list preferences at > https://mailman.amsat.org -- Jonathan Brandenburg Radio Amateur Satellite Corporation 1-214-213-1066

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Pacsat dev mtg 4/6/2023
by Bill 06 Apr '23

06 Apr '23

Thu, Apr 6, 2023 7:00 PM - 9:00 PM (CDT) Please join my meeting from your computer, tablet or smartphone. https://meet.goto.com/325976013 You can also dial in using your phone. (For supported devices, tap a one-touch number below to join instantly.) United States: +1 (571) 317-3122 - One-touch: tel:+15713173122,,325976013# Access Code: 325-976-013 Get the app now and be ready when your first meeting starts: https://meet.goto.com/install

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Filesystem interface to mram
by Corey Minyard 04 Apr '23

04 Apr '23

I have integrated the Reliance Edge filesystem into the PacSatSw repository in the "filesystem" branch. However, it is still missing the lower level interface to the mram devices. Are we using the mram code in the deviceSupport directory? If so, the read and write operations (readMRAMWord, writeMRAMWord) don't have prototypes in the header. But I can fix that and integrate. Jonathan, I guess I'll need a launchpad and a board with the mram, since the qemu stuff didn't work out. -corey

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