Also, make any access to that variable atomic by wrapping the access in interrupts()/noInterrupts() calls so the interrupt cannot change things half way through your statement.

If it's an 8-bit variable a standard read or write is atomic anyway so,

volatile byte var;

x = var;

is OK but

var++;

is not atomic and needs to be protected.

As you have an int (two bytes on most Arduinos) you have to protect all access to it.


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Rob

Are you targeting the Arduino 1.5x IDE as the development environment for the Black Diamond?

We definitely want the board to work with the standard toolchain, that said personally I would never use the IDE so using AS6 and/or one of the great VS/CB/Eclipse plugins would be my preference. I think Paul (Rockwallaby) has worked with Jantje's plugin and knows that pretty well.

Bottom line is that if we make that end of the hardware the same as the Due all that should fall into place. Toolchains are not my strong point, this is probably one area it will be nice to have another conspirator developer.

EEProm for storing startup/calibration constants.

We are using 2 Lattice MachX02 programmable logic devices, each has the capability of allowing the "user" to use some of the internal flash memory as an EEPROM substitute. This should fulfil this function. Also the the CPU's internal "general purpose backup registers"  and (hopefully) the external SRAM are battery backed and can be used for semi-volatile data.

Can you share a price ballpark figure?

Not yet, Paul is working on an initial BOM, we need to know a rough cost before proceeding because so far it's been a nerd's wish list design with little thought to cost, but of course if it's too expensive it will never fly. Hopefully we'll know in a day or two.

I wouldn't mind collaborating with you folks, let me know!

Sure FM, you've got good design experience, what area(s) are you interested in?

Paul and I have been driving this for a few weeks now but I really feel it needs a certain critical mass of involved people so any experienced developer is welcome. At present it's all hardware but that focus will change to be mostly software at some point with a lot of low-level drivers and libraries to write. And then we need a couple of kick-arse plugin boards.

I don't even want to think about manufacture, testing and sales.

BTW this will all be open source when stable.

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Rob

Have a look here

http://majolsurf.net/wordpress/

and maybe here

http://www.artekit.eu/products/devboards/ak-machx02-7000/

I'll be getting the Artekit board when it's available, hopefully in a few days.

I have decided to use the Lattice MachX02 chips, but to be honest I think you will get better support with the Altera/Xilinx chips as they both have pretty active forums.

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Rob

As many will know fellow member Rockwallaby and I have been working on a new ARM-based controller board that will be an Arduino Due workalike but with a lot more IO and with most of the Due’s “hidden” features broken out.

The design is progressing well with schematics and PCB layout slowly becoming firm, and while we are not ready to release full details at this point the following is a quick list of the main features.

•   Atmel SAM3X8E processor, same as Arduino Due.
•   External memory support, 16-bit data, 20-bit address.
•   On-board 2MB SRAM.
•   Switching primary regulator can handle VIN of 7-30V and supply 2A.
•   3v3 system but a lot of support for 5v.
•   120-pin backplane with 4 addressable slots and optional card guides for mechanical stability.
•   Control over power to backplane slots and shutdown/wake up of entire system.
•   Native high-speed 4-bit support for microSD cards.
•   Native Ethernet support with PHY and magjack.
•   USB host interface with micro AB socket.
•   On-board transceivers and/or buffers for RS-232, RS-485, 2x CAN, LIN, 1-WIRE, TTL serial, 2x SMBus/I2C.
•   Where appropriate all serial IO selectable to be 5v or 3v3.
•   XBEE format socket for RF modules including those for XBEE, Bluetooth, and WiFi.
•   52 of the SAM’s native digital IO pins supported on backplane.
•   8 high-current (24mA) GPIO signals on external IO expander. Can be 5v or 3v3.
•   8 analogue inputs on external ADC (internal ADC not used), 12-bit resolution standard but 14- and 16-bit optional. 0V to 5V, 0V to 10V, ±5V or ±10V, single ended or differential. Protected to ±25v.
•   Provision to mount a 4D Systems .96” OLED directly on the board. 96x64 pixels with 65K colours. Can be used for debugging or a simple user interface.
•   Provision for remote and/or larger displays with a 4D Systems-compatible header.
•   3 user push buttons mounted below the OLED for general-purpose or simple menu input.
•   2 external options for the RTC oscillator, standard crystal or TCXO (Temperature Controlled Crystal Oscillator).
•   On-board battery backup for RTC and external RAM.
•   CPU supervisor chip with advanced power-lost warning and battery changeover.
•   Fits a standard Hammond enclosure.

The design can still be modified so if you are interested in this board either as a potential user or co developer email Rob (rob@robgray.com).

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Rob

an opamp can "deliver" an almost infinite number of "values", all it does is amplify and/or shift what you give it.

If you give it 16 different levels you will get 16 different levels out of it that may or may not be the same as the inputs depending on how you construct the circuit.

What exactly are these values you need, 16 equally spaced from 2v7 to 3v9?

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Rob

Have a  look at the ATtiny1634, still 20 pins but I2C, TWO serial ports and a 12-channel ADC, I suspect that the 2313 won't be used much in future

All it's missing I think is real SPI.

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Rob

Looks like you've got a proper switching regulator there feilipu, that will help with high VINs, 'bout Arduino designs started doing this.

What's the 2x5 pads just to the left of the 1284, JTAG header?

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Rob

There are maybe 2-3 simple schedulers around I think.

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Rob

Have struggled with the Arduino IDE  :-/ I am designing a replacement for that in my head. Eesh!

There are 3-4 nice alternatives already so don't knock yourself out doing another one.

focus on the Arduino programming

Yes it's easy to get distracted making tools and get nothing done on the original project.

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Rob

That's quite nice, which way does the data entry work, I assume clicking on the "dots" in the graphic changes the code snippet.

Also can it generate a 2-dimensional array for X number of chars?

Doesn't matter what you do, people always want more eh
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Rob

A standard USB cable, mini B on the Arduino end IIRC.

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Rob

Great stuff, and at Bletchly as well, fairly appropriate.

And the guys that did a lot of that stuff got no public recognition I suppose because it was secret.

If I get back to the UK I'll have to visit the TNMOC.

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Rob

resistor jumpers for breadboard interfacing and to greatly improve the life of your resistors in daily experimentation

eh?

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Rob

That looks like a lot of fun, pity I couldn't get there.

A lot of retro stuff it seems, is that all us old farts travelling down memory lane? Although it seems the youngsters still get a kick out of Pong et al.

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Rob

i spend 3 months  try to connect them and i fail

All for the sake of some proper test equipment, a $149 (heck I think you can get them for $20) logic analyser would have got to the bottom of this in 5 minutes.

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Rob