Starting up... again... how to program blank chips?

New to XMOS and XCore? Get started here.
User avatar
williamk
Experienced Member
Posts: 114
Joined: Fri Oct 01, 2010 7:47 pm

Re: Starting up... again... how to program blank chips?

Postby williamk » Mon Sep 19, 2011 4:41 pm

Ah, I forgot, the 1V regulator... :oops: guess that would be needed on the shield, as the Arduino board doesn't supply that.

Wk
Wusik Dot Com (http://www.Wusik.com)
William-K.com (http://www.William-K.com)
User avatar
williamk
Experienced Member
Posts: 114
Joined: Fri Oct 01, 2010 7:47 pm

Postby williamk » Mon Sep 19, 2011 4:57 pm

Ok, here's the Arduino MEGA2560, which has 256 KB of flash space. Enough for anything, and it has all the power requirements besides the 1V regulator. (unless the current draw of any of the 5V/3V3 regulators are not enought)

To talk to the Arduino during real-time mode, 8-bit parallel communication could be used by using multiple I/O pins on the Arduino x XMOS, which is much faster, instead of the slower SPI.

In case people never see an Arduino MEGA2560...

http://arduino.cc/en/Main/ArduinoBoardMega2560

Wk
Wusik Dot Com (http://www.Wusik.com)
William-K.com (http://www.William-K.com)
MaxFlashrom
Experienced Member
Posts: 82
Joined: Fri Nov 05, 2010 2:59 pm

Postby MaxFlashrom » Mon Sep 19, 2011 6:06 pm

williamk wrote:Biano, thank you for been patient with me, of course SPI Flash wouldn't cope with a 100 MHz clock.
William, I'm not sure why you think SPI flash wouldn't cope with a 100MHz clock. Macronix make several SPI flash devices that can be read at 108MHz. Of course the Xcore may not be able to read this fast. Experiments with raising the reference clock frequency suggest that this may be possible.

Many support x1 as well as x4 bit reading, so can boot with the default XMOS loader in slow read mode and faster in x4 mode later by an application. x4 bit reading can be performed at 70MHz. Some will output on both clock edges too, like DDR2.

See http://www.macronix.com/QuickPlace/hq/P ... enDocument

And, no, I'm not on commission from them!
Bianco wrote:
williamk wrote:Quick question, is the following SPI Flash doable for the XMOS chip auto-boot-from-external-flash? ;-) Txs.

http://www.sparkfun.com/products/301

Wk
That's a rather large flash chip you got there (for a very decent price).
I doubt it is supported out of the box. You will problably need to write your own flash description file for the xflash tool. See chapter 10 of the Tools User Guide
That Atmel AT45DB161D 16Mbit Dataflash series flash is somewhat peculiar. It has irregular sector sizes and the option of 528, rather than 512 byte pages by default. This magic number greater than a power of 2 is something of a mystery, but it does mean you can actually get just over 3% more out of the chip. As it has 4096 pages, if you use the 528 byte page size this gives 17,301,504 bits or 16.5Mbit(power of 2, not 10)
It also has RAM buffers within; this is not bad, just different. The supply chain lead-time for Atmel devices is somewhat erratic currently.

I'd have to study the datasheet more closely to determine if it's compatible with the xflash library. In any case it probably would not be my first choice, as I like the look of those Macronix.

Max.
User avatar
williamk
Experienced Member
Posts: 114
Joined: Fri Oct 01, 2010 7:47 pm

Postby williamk » Tue Sep 20, 2011 2:13 am

BTW: could somehow help me out and point me to a 16-bit DAC I could find on eBay that would be OK/GOOD and also work with the XMOS chip? :oops:

Don't bother about other distributors, as I'm in Brazil, and right now I'm only getting things on eBay as its easier and has low-shipping options.

Thanks.

Wk
Wusik Dot Com (http://www.Wusik.com)
William-K.com (http://www.William-K.com)
User avatar
williamk
Experienced Member
Posts: 114
Joined: Fri Oct 01, 2010 7:47 pm

Postby williamk » Wed Sep 21, 2011 1:16 pm

Slowly the people on the Arduino Forum is starting to like the idea of a XMOS Shield for the Arduino. :mrgreen:

Wk
Wusik Dot Com (http://www.Wusik.com)
William-K.com (http://www.William-K.com)

Who is online

Users browsing this forum: No registered users and 3 guests