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Yes, the radio based on the new board will be firmware compatible if you make your radio by having the same type of LCD, same pinouts for all the pots and switches, ... you should make your shield board like Brent's 9x shield.

Brent, does (sky-core9x + 9x shield) combination cost less than your old sky9x board marketed for 9x board upgrade/replacement?
Based on my simple math, it will cost more if you make the new sky-core9x functionally compatible with the old sky9x board unless you make the new board to meet the economies of scale.

This "core" board uses the same processor as the Taranis so it shouldn't take too much effort to tie all the drivers from ersky9x for the Taranis together to produce a version of ersky9x for this board.
There is also the possibility of using this "core" board with a serial connection to the existing 9X board and using all the stick, pot, switch and buttons and the LCD left on that. I already have the code working at both ends for this.

Mike.

Does it really make sense to go for the 512K version of the CPU (as in Taranis) instead of 1M ? I mean, price for 1M version will almost be the same as 512K. But 1M of flash could possibly give more opportunities for some applications.

Brent, are those 0.1" header pins aligned to 0.1" grid of your layout editor?
If all the header pins are aligned to the grid, I can make a shield board using a 0.1" perf board.

What's in the other side of the PCB?
You may put soldering pads/pins for surface mounted JST connectors that can be used for 9x pots/sw connections so that DIY's can solder the connectors if they want. It would be even better if you put soldering pads for an LCD connector and caps for LCD charge pump circuit if space permits.

A board like this has far more applications that it could be used on, Than a dedicated 9x board. The sky board cost way to much to make,
dont forget the time to solder in all the through hole parts , program , and then test all the inputs and output functions..and because of the high part /track density , there was at least a 10% failure rate ... ( I have a box of them)

The PCB designs for the shield boards would be available for people to get made / modify themselves.

The header pins are on 0.1 grid , so yes you can plug into a standard perf board.
The other side of the board is the Ground plane. Cant do to much here without compromising the ground connections.
There are so many LCDs types out there , I thought it better that I provide multi purpose connection.

The Size of the ARM chip will depend on who and how many boards are made ...but yes the largest memory chip is a good idea if it can be done.

If there is enough interest , then maybe a large run can be made ....if not then maybe just blank pcbs could be sold.

-Brent

SkyNorth wrote: The Size of the ARM chip will depend on who and how many boards are made ...but yes the largest memory chip is a good idea if it can be done.

If it can, why not? I had the m128 on both my 9x radios, Now I'm replacing them with the atmega2561. I wish now I installed the better chip before. It would have saved time, money, and trouble.. I did learn some more though.

If there is enough interest , then maybe a large run can be made ....if not then maybe just blank pcbs could be sold.

-Brent

Or both? maybe a kit?

Thanks Brent

João

The 100pcs price on the 1M part is $19.75 CDN - $26 single piece ..
The 100pcs price on the 512K part is $11.85 CDN - $16 single

Seems high for the 1M part, I just looked on Mouser (UK) and the 1M part is not at such a high premium there.
100 off £6.98 against £5.64 for the 512K part.
STM32F407:
1M - 100 off - £5.99
512K - 100 off - £7.18

The '407 has more RAM (192K to 128K), runs up to 168MHz (not 120MHz), is a Cortex-M4 with FPU (not Cortex-M3, no FPU).
It does run M3 code unchanged, and the peripheral mapping is pretty much the same.
(FPU = Floating Point Unit).

I would suggest the '407, even at 512K flash, is actually a more powerful part. Ersky9x is currently using less than 190K flash, of which 32K is the bootloader.

Mike.

But more RAM is always good, right?

João

Yep , the 407 is priced better .. still expensive here ... the Canadian Dollar is way down against the US..
$1 CDN = $0.82 USD

We have a crazy situation with currency exchange rate nowadays. So here are today's prices - seem to be quite cheap:

STM32F407VGT6 (1M flash) = $8
STM32F407VET6 (512K flash) = $7.50

STM32F205RGT6 (1M flash) = $7
STM32F205RET6 (512K flash) = $5.70

All prices are in USD. The positive thing about it is that these prices are valid even for small orders (starting already at 10 pieces, or so).

If needed, I can purchase these locally and send them over to someone.

BTW, I can also check locally for PCB manufacturing & assembly service. I know it is quite expensive for small batches (I checked for 10pcs not so long ago, and even oshpark was more attractive than the local service). But there are significant discounts for larger volumes. So it may appear to be very competitive for a batch of a few hundreds pieces.

Shipping should be manageable (if given some time), as me or my colleagues are traveling to EU and US on a regular basis.

Thats a big difference....Digikey is not the cheapest ..thats for sure ...
North America is just too expensive to MFG this type of product ...
Thats why the whole thing needs to be made offshore...

-Brent

STM32F discovery board? I don't think it will fit to 9x case but the price is good.
http://www.st.com/st-web-ui/static/acti ... 039084.pdf
http://www.ebay.com/itm/ST-STM32F4-Disc ... 256c55e6e9

Hmmm, no RTC? and no SD Card as far as I can see. I like the OTG feature but I guess Brent's board also has it..

João

There is a space for a 32kHz crystal for a RTC, but the Vbat supply is hardwired to VDD making that difficult to use. There is no built in SDcard either. I did look at some of these type of board but didn't find anything really like what we want.

Thinking further about using the 'CORE' board over serial to use the M64(/128/2561) as an I/O processor, I can actually use a Taranis board with its serial port to get the code up and running before we have prototypes of of the 'CORE' board.

Mike.

STM32F4xx devices have Real Time Clock (RTC) inside, with support of internal calibrated 32768 Hz oscillator or external (more accurate) 32768 Hz oscillator.
RTC peripheral has also backup register support, which means that when you reset MCU, registers are not reset or if power is off and you have battery connected on Vbat pin, clock is still working. VBAT on F4-Discovery is not brought out to the headers. The only way is to remove R26 and somehow wire up the battery to its pad connected to VBAT.

This LCD looks perfect for a 9x Shield ... or any other project ..
Having pins and not a FPC connector , means anybody could solder it in....
http://www.buydisplay.com/default/2-8-i ... k-on-white

Backlight current is a bit high at 60mA, but otherwise looks OK.
The control chip is the same make as on the Taranis Plus, so the driver code shouldn't be too difficult to sort out.

Mike.

UC1701 and ST7565 LCD controllers are register compatible - i.e. you can use this LCD without modifying 9x LCD driver code.
If you need just one unit, it's cheaper if you buy it from buydisplay.com (EastRising) eBay store.
http://www.ebay.com/itm/Slim-2-8-128x64 ... 43c39e2d5d

Never buy white-on-blue LCD - it looks cool but it has a very poor daylight readability.
I've used various EastRising LCD modules for vintage transmitter retrofitting project and I personally like yellow-green backlight.
You can ask a specific backlight color when you place an order.

BTW, I doubt that Taranis Plus has an UC1701 controller since the max resolution supported by this controller is 132x65.

He said same make, not same exact model

Here is how the board is coming along..

I added a spot on the back to add some Open collector drivers .. for Haptic , LED backlight , and relay drive. There are solder pads
to access the required pins...

The USB signals are now brought out to a 5 pin header on the the 0.100" grid.

-Brent

Brent, looks good - can't wait!
It would be nice if you can add 6 more soldering pads for an external MicroSD card adapter.
Even though on board SD card can be accessible through the USB port, an external adapter allows us removing/inserting the card without opening the case.
It looks like potential spot is taken by the open collector drivers
If you can't put them both, I vote for the SD card signals rather than unconnected open collector drivers since they can easily be added to a shield.

There is a "spare" SPI interface brought out to some of the pin headers.

Mike.

Is the "spare" SPI interface very same SPI interface used for on-board SD card?
If not, I need to modify the firmware to hook up an external SD card adapter, right?

I would have to make the board longer to fit a connector ... This is a full speed SD card interface , it uses 4 data lines , and needs a 10 pin connector.
I'll have a look....

I see - it's not using an SPI interface.
I think narrow-pitch (0.05") 9 soldering pads for 9-wire ribbon cable are good enough for SDIO interface if you can put them without increasing the length.
Can you move the processor to slight left to make a room for the soldering pads ?

Here is how it is shaping up.. There is now a spot for a remote SD card and USB ports . On board RTC Battery. , and drive outputs for Haptic , LED , AUX.
Card is 3.5" x 2" , can be shaved down to just under 1.9"

-Brent

Brent, that is looking reeeeaaally good. Onboard RTC batt holder is a very nice addition, as is the control of backlight and haptic.. I gotta say, it looks fantastic..

João

EDIT: do the mounting holes match the ones on the 9x? If so, which ones? Main or back board?

Fortunately I saved one 9x case and a new set of sticks.
SM

You will also need the mainboard and the backboard I think
But I think this little board could be a complete tx on its own..

João