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Re: Si5351 Programming Flowchart

Pavel Milanes Costa
 

开云体育

Hi to all.

The flowchat is a instructive guide for the curious of how to doit without float point math and an expression of the KISS principle.

It's just a cheat sheet to learn from.

The trick is to understand the way he (like Gerry) find a, b and c not needing floating point math. (for the PLL/VCO Msynths case is)

a = int(Fvco/xtal)

b = Fvco % xtal (module, aka: rest of the division)

c = xtal

For example Gerry do a do..while to find a value of b/c that match the allowed size of c, he need it because he is working with the output Msynth dividers not the PLL/VCO Msynth, in his case c = fout and is variable.

In the later case (moving the PLL/VCO Msynth, output Msynth dividers are fixed) c is fixed and equal to the Xtal and we know it already then we can do a simple x >> 5 to both b/c to retain maximum accuracy and make it fit on the register. If we do that just set the output Msynth divider to a integer & even value to minimize jitter or phase noise.

In Gerry routines he fixes the VCO and moves the output divider Msynth and that make some jitter or phase noise (almost negligible in real applications, I know) and makes 3 outs from just one fixed VCO and does not handles the R values or the DIV_BY4 feature limiting the full range of output frequencies (not needed on his target application, I know).

This is just another way of doing things, a way that can be better understood because it uses a simple and elegant image (flowchart), to make life (& code) easier (& smaller)...

BTW I found a possible bug that can haunt more than one in the routines of computing MSx_P2. A tip for the "math" experts... and a common fault.

As per the data:

MSx_P2 = 128 * b - c * floor (128 * b / c)

Right?

It's very tempting to reduce it but the floor functions is in there... let see... floor is the lower integer for that float number, hum...

Floor is on the C of Gcc the compiler used by the arduino project but it implies the use of floating point math hence bigger code, just eliminate it and do the math, let try to reduce it...

MSx_P2 = (128 * b) - (c * 128 * b / c)
MSx_P2 = (128 * b) - (128 * b) ---> (c is eliminated as it's * and /? in the expression)
MSx_P2 = 128 * (b - b) ---> ( hum....)
MSx_P2 = 128 * 0 ---> (HUMMMM!!!)
MSx_P2 = 0 ---> (WTF !!!!)

Doing some math and wall head-hiting you can conclude that the floor function is instructing you to IGNORE the use of fractions and then you get a value in MSx_P2 that it related to the amount of error or rest of division of doing things (math) with integers... hence the floor function... forcing you to use just integers... nice.

For example Gerry users in his code this:

msxp2 = 128 * msb - 128 * msb / msc * msc;

If you play that same function with human and integer rules it play well and result is different from zero, but if you use floating point math it always equals to ZERO!

Let's play it with me in full integer math

let's say msb = 900 and msc = 1000

msxp2 = 128 * 900 - 128 * 900 / 1000 * 1000;
msxp2 = 115200 - 115200 / 1000 * 1000;
msxp2 = 115200 - 115 * 1000;?? // <<<<=== here is the floor in action (result in float is 115.200 we get it down to 115, all with the magic of integer math)
msxp2 = 115200 - 115000;
msxp2 = 200;

In this case 200 is a relation of the error of using integer math... interesting, mind you how the chip use it internally

For correctness and just to be sure to maintain the best accuracy you must get sure the compiler do the 128*b/c * c in the correct order, that is as per Gerry code fragment:

msxp2 = 128 * msb - 128 * msb / msc * msc;

Must be forced to execute in the correct order by placing some parenthesis to maintain more accuracy.

msxp2 = 128 * msb - ((128 * msb) / msc) * msc;

Firmware size impact is unchanged, compiled code is the same (sha256sum) with and without the parenthesis so GCC compiler is doing he job right, beware of others...

I mentioned this because I have a ham fellow in university (freshman) that hit his head against this wall a few times, "that's impossible, that has no sense.... MSx_P2 is always zero..." he said...

Just my two cents for other that may be in troubles like this understanding the chip.

Cheers, Pavel.

El 12/02/18 a las 12:07, JuanCarlos Berberena Gonzalez escribió:

Hi Guys
A weeks ago Josué Marin-CO7RR- sent me this information to share with my group.
I am only try to be a good 'USER" testing some interesting project I can get on the web and afterward share it with my group.
Now Pavel-CO7WT- sent me this link and I think is a good idea to share with all of you.
?


It is a Josué Marin email address
marinjosue75atgmaildotcom?
Qrv's
73's Jc

Re: Mailbox metal case 3x6x9 inch #ubitx

KC9SGV
 

开云体育

Funny as hell ?!!
But a good, solution.

KC9SGV


On Feb 12, 2018, at 2:33 PM, Doug W <dougwilner@...> wrote:

so do you call QC or just put the flag up and wait...

Re: uBITx For Sale

Stephen Johnson
 

I can use everything except the DSP filter if still available.

Steve, N2FT

On Mon, Feb 12, 2018 at 3:09 PM, Glenn AE0Q <ae0q@...> wrote:
I just today received my uBITx (ordered on 19 Dec) but things have changed and I don't have time for the project.

I've collected some things I was going to use to build it, all is for sale.

uBITx? unopened except for photos? ?$109

Adafruit 10k Log pot (with 1/4" dia shaft) and 2 black knobs (blue stripe)? $5.00

SOTABeams CW DSP Audio Filter? $42

Beautiful aluminum enclosure (2.4" x 6.22" x 7.2" inside dimensions)? $20
See the ebay link for assembled photos of the box.


Photos of all attached.

Would like to sell all together but not necessary.

Glenn AE0Q


Re: uBITx For Sale

 

I would like to buy your uBitx.

Please send remittance details.

Bob N1ETS
Re: Si5351 Programming Flowchart

 

Yup, not much point in getting too carried away in creating a VFO for the Bitx40.
Initial accuracy of the si5351bx routines can be calibrated to be quite good by adjusting si5351bx_vcoa
But a slight change in temperature and the 25mhz reference will drift a few hz,
so stability will be an issue

If an application comes up where greater stability is required,
the 25mhz (or 27mhz) reference could come from an ocxo or tcxo, or be GPS disciplined,
or perhaps you constantly adjust a knob for zero-beat with a known accurate radio station such as wwv.

Jerry, KE7ER


On Mon, Feb 12, 2018 at 12:56 pm, Pavel Milanes Costa wrote:
El 12/02/18 a las 15:35, Jerry Gaffke via Groups.Io escribió:
Calculations within the si5351bx routines are much better than than 1ppm accurate, perhaps more like 0.01ppm.
As I recall, the math was accurate within 0.2hz when doing calculations for a high side vfo on the Bitx40 of 19mhz.
If the math/hardware has a better accuracy than the Xtal itself then you have at the output just the stability of the Xtal... right?
Re: Blown by nearby transceiver #bitx40help

 

开云体育

Try “mu metal” shielding found on Amazon

AA7GW

On Feb 12, 2018, at 1:28 PM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:

Good point, if we're worried about magnetic field coupling then tinfoil won't do much good.
I'm not sure exactly how the power to blow 1/4 Watt resistors would be communicated,
was guessing it might be straight magnetic coupling like a transformer, though could be electromagnetic.
I doubt it is straight electrostatic, not enough current with no conductor between unless the air ionizes as in a lightning bolt.
If electromagnetic (radio waves), a Faraday cage around the radio such as that tinfoil is in order,
and this is the sort of shielding usually found in commercial gear.? Such shielding might help
resolve the problem of hearing audio tones from the 16mhz Nano oscillator, or noise from
nearby computers and power supplies.

My rig is stitting out open-faced on a piece of plywood, front and back panels of scrap PC screwed to the plywood,
the main board has the standoffs installed upside down so the 4-40 threads are held in place by holes drilled into the wood.
Works fine, though I have a quiet environment.? Easy to work on, I can just pick the board up and pop the connectors off.

When posting that original tinfoil hat comment my thought was:
? ? "If it can do that to 1/4 Watt resistors,?what can it do to my brain?"
Perhaps we will learn that there was a cabled connection, and this is all moot.

I spent about 6 hours with cell phone at my ear a couple days ago trying to sort out?
some issues with our Verizon cellphone account.? ?I really should have been using a headset.
I have heard occasional reports like Raj's though am not aware of a definitive study.
Am thinking a 4 Watt transmitter 1/4" from my brain for long periods is best avoided.

Jerry, KE7ER


On Mon, Feb 12, 2018 at 10:57 am, Arv Evans wrote:
While tinfoil (even the tinfoil hat) can lessen exposure to static charges, how
much effect does it have on electro-magnetic energy.? Seems that a thick steel
chassis (or hat)? might be better for limiting both ES and EM signal levels.
Re: wrong frequency after software change. #ubitx

 

That should read ‘rewiring’ Not rewriting!


On Tue, 13 Feb 2018 at 9:54 AM, Mike Woods <mhwoods@...> wrote:
Michael

The uBITx and the BITx40 have different circuitry.? In particular the uBITx has 2 IF stages (45MHz and 12MHz) whereas the BITx40 only has one at 12 MHz.? Some changes would be required to the software before the uBITx software will work on the BITx40.? Also some rewriting would be required as different pin outs are used (particularly if the BITx40 has been modified with Allard mods.

I am working on changing over one of my BITx40s to run on uBITx.? I will report on progress to the group.

There is no difference between Raduino devices except the header confuguration.? You should use either the HF Signals BITx4o sketch or the improved sketch from Allard, at least in the short term.

Mike ZL1AXG



On Tue, 13 Feb 2018 at 6:27 AM, Michael Shreeve <shreevester@...> wrote:
Another strange twist which may be related. I changed a BITX40 rad to uBITX Raduino. Hardware change, you remove the 5 pin plug and put a header in its place. I really looked hard for any other differences in Hardware. Saw none. So, I programed with original software. Crazy, but LSB is USB on 80 and 40 (up to 10mhz) and other than that, seems stable and might be on freq. So, I tried Ians latest 1.01 and LSB is correct, USB is correct, have control also, but freq is off about 400khz. So, found an EEPROM WIPE routine, says it works for all size eproms, and did the wipe. No luck. Still off, I re-loaded the original Ashhar software stil backwards. Thinking I would need to use memory manager but not sure I have the skills. Any ideas ??

On Mon, Feb 12, 2018 at 9:01 AM, at91r40008 <yvon@...> wrote:
Thank you Jack, the problem is that it shows all the same name because it takes the project
name uBitx20. Every project I downloaded has a new folder name but inside
Arduino it shows uBitx20.
That is why I am going to rename them each time I download one.
--
73, Yvon NU6I




--
Michael Shreeve N6GRG

Anderson, CA 96007
530-410-8678
"Don't worry about a thing, 'Cause every little thing gonna be all right!" -Bob Marley
Re: Si5351 Programming Flowchart

Pavel Milanes Costa
 

El 12/02/18 a las 15:35, Jerry Gaffke via Groups.Io escribió:
Calculations within the si5351bx routines are much better than than 1ppm accurate, perhaps more like 0.01ppm.
As I recall, the math was accurate within 0.2hz when doing calculations for a high side vfo on the Bitx40 of 19mhz.
If the math/hardware has a better accuracy than the Xtal itself then you have at the output just the stability of the Xtal... right?

73 Pavel CO7WT
Re: wrong frequency after software change. #ubitx

 

Michael

The uBITx and the BITx40 have different circuitry.? In particular the uBITx has 2 IF stages (45MHz and 12MHz) whereas the BITx40 only has one at 12 MHz.? Some changes would be required to the software before the uBITx software will work on the BITx40.? Also some rewriting would be required as different pin outs are used (particularly if the BITx40 has been modified with Allard mods.

I am working on changing over one of my BITx40s to run on uBITx.? I will report on progress to the group.

There is no difference between Raduino devices except the header confuguration.? You should use either the HF Signals BITx4o sketch or the improved sketch from Allard, at least in the short term.

Mike ZL1AXG



On Tue, 13 Feb 2018 at 6:27 AM, Michael Shreeve <shreevester@...> wrote:
Another strange twist which may be related. I changed a BITX40 rad to uBITX Raduino. Hardware change, you remove the 5 pin plug and put a header in its place. I really looked hard for any other differences in Hardware. Saw none. So, I programed with original software. Crazy, but LSB is USB on 80 and 40 (up to 10mhz) and other than that, seems stable and might be on freq. So, I tried Ians latest 1.01 and LSB is correct, USB is correct, have control also, but freq is off about 400khz. So, found an EEPROM WIPE routine, says it works for all size eproms, and did the wipe. No luck. Still off, I re-loaded the original Ashhar software stil backwards. Thinking I would need to use memory manager but not sure I have the skills. Any ideas ??

On Mon, Feb 12, 2018 at 9:01 AM, at91r40008 <yvon@...> wrote:
Thank you Jack, the problem is that it shows all the same name because it takes the project
name uBitx20. Every project I downloaded has a new folder name but inside
Arduino it shows uBitx20.
That is why I am going to rename them each time I download one.
--
73, Yvon NU6I




--
Michael Shreeve N6GRG

Anderson, CA 96007
530-410-8678
"Don't worry about a thing, 'Cause every little thing gonna be all right!" -Bob Marley
Re: Si5351 Programming Flowchart

 

Calculations within the si5351bx routines are much better than than 1ppm accurate, perhaps more like 0.01ppm.
As I recall, the math was accurate within 0.2hz when doing calculations for a high side vfo on the Bitx40 of 19mhz.?


On Mon, Feb 12, 2018 at 09:48 am, Jerry Gaffke wrote:
The accuracy of the calculations is down around 1ppm, considerably better than the stability of the 25mhz reference oscillator.
Re: Blown by nearby transceiver #bitx40help

 

Good point, if we're worried about magnetic field coupling then tinfoil won't do much good.
I'm not sure exactly how the power to blow 1/4 Watt resistors would be communicated,
was guessing it might be straight magnetic coupling like a transformer, though could be electromagnetic.
I doubt it is straight electrostatic, not enough current with no conductor between unless the air ionizes as in a lightning bolt.
If electromagnetic (radio waves), a Faraday cage around the radio such as that tinfoil is in order,
and this is the sort of shielding usually found in commercial gear.? Such shielding might help
resolve the problem of hearing audio tones from the 16mhz Nano oscillator, or noise from
nearby computers and power supplies.

My rig is stitting out open-faced on a piece of plywood, front and back panels of scrap PC screwed to the plywood,
the main board has the standoffs installed upside down so the 4-40 threads are held in place by holes drilled into the wood.
Works fine, though I have a quiet environment.? Easy to work on, I can just pick the board up and pop the connectors off.

When posting that original tinfoil hat comment my thought was:
? ? "If it can do that to 1/4 Watt resistors,?what can it do to my brain?"
Perhaps we will learn that there was a cabled connection, and this is all moot.

I spent about 6 hours with cell phone at my ear a couple days ago trying to sort out?
some issues with our Verizon cellphone account.? ?I really should have been using a headset.
I have heard occasional reports like Raj's though am not aware of a definitive study.
Am thinking a 4 Watt transmitter 1/4" from my brain for long periods is best avoided.

Jerry, KE7ER


On Mon, Feb 12, 2018 at 10:57 am, Arv Evans wrote:
While tinfoil (even the tinfoil hat) can lessen exposure to static charges, how
much effect does it have on electro-magnetic energy.? Seems that a thick steel
chassis (or hat)? might be better for limiting both ES and EM signal levels.
RadI2Cino boards temporarily sold out! #ubitx

 

Ladies & Gentlemen, the response to this offering has been overwhelming.? The initial run of boards, both bare boards and the option 2 boards with the SMD semiconductors already installed from this initial offering are SOLD OUT.? More boards are on order but due to the Chinese New Year they won't be shipping until around the end of the month.

We ask that you please hold all inquiries and orders until I re-announce the availability of the next batch.? We have decided NOT to allow any pre-ordering to avoid the tremendous overhead involved in keeping track of incoming orders while trying to do other design work.?

Thank you very much for your understanding and we are very sorry for the inconvenience.? The RadI2Cino boards will again be available just not immediately.

Jim Sheldon - W0EB
uBITx For Sale

Glenn AE0Q
 

I just today received my uBITx (ordered on 19 Dec) but things have changed and I don't have time for the project.

I've collected some things I was going to use to build it, all is for sale.

uBITx? unopened except for photos? ?$109

Adafruit 10k Log pot (with 1/4" dia shaft) and 2 black knobs (blue stripe)? $5.00

SOTABeams CW DSP Audio Filter? $42

Beautiful aluminum enclosure (2.4" x 6.22" x 7.2" inside dimensions)? $20
See the ebay link for assembled photos of the box.


Photos of all attached.

Would like to sell all together but not necessary.

Glenn AE0Q

uBITx_Adafruit_pot_knobs_SOTABeams_filter.jpg
uBITx_Adafruit_pot_knobs.jpg
uBITx_SOTABeams_filter.jpg
uBITx_box 002.jpg
uBITx_box 003.jpg
uBITx_box 004.jpg
uBITx_box 005.jpg
uBITx_box 006.jpg

Re: Second batch of uBITX shipping? #ubitx

 

开云体育

Ordered on 18 Dec.? Shipped 7 Feb.? Received 11 Feb.

Mike

K5ESS

?

From: [email protected] [mailto:[email protected]] On Behalf Of Gary Shriver
Sent: Monday, February 12, 2018 12:58 PM
To: [email protected]
Subject: Re: [BITX20] Second batch of uBITX shipping?

?

When did you order?

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of K5ESS
Sent: Monday, February 12, 2018 10:33 AM
To: [email protected]
Subject: Re: [BITX20] Second batch of uBITX shipping?

?

Got my uBITX yesterday via DHL (yes on Sunday). Didn’t have to sign.? Just a big yellow envelope left at my doorstep.

Mike

K5ESS

?

From: [email protected] [mailto:[email protected]] On Behalf Of Art Howard
Sent: Monday, February 12, 2018 8:52 AM
To: [email protected]
Subject: Re: [BITX20] Second batch of uBITX shipping?

?

Steve

?I should get mine today I noticed that it's in Minneapolis now.

? Do you know if the package has to be signed for ?

Art

?

On 12 Feb 2018 7:59 am, "S. Porter" <srporter@...> wrote:

Art,

Just got off the phone with a DHL rep who said DHL will deliver here, not USPS. Your mileage may vary. The package is on the move again this morning! :-)

73,
Steve

On Sat, Feb 10, 2018 at 04:08 pm, Art Howard wrote:

I also ordered mine on the 18th and mine is also sitting in Cincinnati for the last day.

?It is indicated that once it hits the USA it is USPS. Was supposed to deliver this last Friday so I figure maybe Tuesday here in Minnesota.

?
Re: Second batch of uBITX shipping? #ubitx

 

Got mine today. ordered December 18th. Arrived at my place via Courier Service?


On 26 Jan 2018 2:37 am, "dj0hf" <dj0hf@...> wrote:
Ordered on the 16th December - Nothing yet.

73
Ian
DJ0HF/G3ULO




Screenshot_20180212-131118.png

Re: Second batch of uBITX shipping? #ubitx

 

It's here...?
Ordered on December 18th.


On 12 Feb 2018 8:51 am, "Art Howard" <k0kuk.vhf@...> wrote:
Steve
?I should get mine today I noticed that it's in Minneapolis now.
? Do you know if the package has to be signed for ?
Art

On 12 Feb 2018 7:59 am, "S. Porter" <srporter@...> wrote:
Art,

Just got off the phone with a DHL rep who said DHL will deliver here, not USPS. Your mileage may vary. The package is on the move again this morning! :-)

73,
Steve

On Sat, Feb 10, 2018 at 04:08 pm, Art Howard wrote:
I also ordered mine on the 18th and mine is also sitting in Cincinnati for the last day.
?It is indicated that once it hits the USA it is USPS. Was supposed to deliver this last Friday so I figure maybe Tuesday here in Minnesota.
?

Screenshot_20180212-131118.png

Re: Second batch of uBITX shipping? #ubitx

S. Porter
 

Art,

Package just arrived via DHL courier.

I did have to sign for it.

73,
Steve
Re: RadI2Cino - I2C replacement for the uBITX Raduino #ubitx

 

Ordering for the option 2 boards is temporarily closed - out of boards to make them with.? The response was far more than expected.? There may be 4 or 5 bare boards (option 1) left but those are rapidly disappearing as well.?

Anticipate more boards in about 15 days but until then the order window is closed.

I'll announce when they are again available in this thread here.

Jim Sheldon, W0EB
Re: Second batch of uBITX shipping? #ubitx

 

开云体育

When did you order?

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of K5ESS
Sent: Monday, February 12, 2018 10:33 AM
To: [email protected]
Subject: Re: [BITX20] Second batch of uBITX shipping?

?

Got my uBITX yesterday via DHL (yes on Sunday). Didn’t have to sign.? Just a big yellow envelope left at my doorstep.

Mike

K5ESS

?

From: [email protected] [mailto:[email protected]] On Behalf Of Art Howard
Sent: Monday, February 12, 2018 8:52 AM
To: [email protected]
Subject: Re: [BITX20] Second batch of uBITX shipping?

?

Steve

?I should get mine today I noticed that it's in Minneapolis now.

? Do you know if the package has to be signed for ?

Art

?

On 12 Feb 2018 7:59 am, "S. Porter" <srporter@...> wrote:

Art,

Just got off the phone with a DHL rep who said DHL will deliver here, not USPS. Your mileage may vary. The package is on the move again this morning! :-)

73,
Steve

On Sat, Feb 10, 2018 at 04:08 pm, Art Howard wrote:

I also ordered mine on the 18th and mine is also sitting in Cincinnati for the last day.

?It is indicated that once it hits the USA it is USPS. Was supposed to deliver this last Friday so I figure maybe Tuesday here in Minnesota.

?
Re: Blown by nearby transceiver #bitx40help

 

Jerry KE7ER

While tinfoil (even the tinfoil hat) can lessen exposure to static charges, how
much effect does it have on electro-magnetic energy.? Seems that a thick steel
chassis (or hat)? might be better for limiting both ES and EM signal levels.

Arv? K7HKL
_._

On Mon, Feb 12, 2018 at 10:54 AM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
Jury is still out as to how those parts got blown, and I am genuinely curious.
Most commercial radio gear that comes in plastic cases uses some sort of thin metallic film
on the interior to provide shielding, and if this is of concern I do think gluing tinfoil to the inside
surface is a reasonable thing to do.

My apologies if anyone was offended by the reference to a tinfoil hat.
Though as Raj has pointed out, that's not necessarily a bad idea either.

Jerry, KE7ER

On Mon, Feb 12, 2018 at 09:18 am, Jack Purdum wrote:
No, I was dead serious.
?
Suggesting that someone has to be crazy to use a plastic case for an xcvr is uncalled for. Much of my work is done with an eye to the ham (or potential ham) who has limited income for our hobby. (See my intro to the Forty-9er article, March, 2016, QST.) There are a lot of people who cannot afford a $50 Hammond aluminum case. There are others who don't have the tools to work with aluminum; even a $30 nibbling tool is out of reach. Some who choose a plastic case may do so for economic reasons, but it could also they want it as light as possible and, when working a SOTA location, they're not overly-concerned about stray RFI. It may be they just like the way a plastic case looks. The popularity of 3-D printed cases is an example. Indeed, we all have read about hams who have mounted their BITX in the plastic case it came in. Others have used cigar boxes. I used an acrylic case for the Forty-9er because I wanted the visitors at the next Field Day to see that a viable rig does not have to be complicated.
?
So, no, I don't think it was called for because there are a lot of viable reasons for not using a metal case and to imply that someone who does needs to wear a foil hat is uncalled for.
?
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