Hi James. I will upload the tmp file again or ping it across by email. Actually I'm pretty sure the data is ok because it did print well once the printer had more juice.
I'm a bit stuck until I get a new core. Slightly embarrassed about the frying the core!
I have decided to rewire again anyway, trying to reduce the footprint. I think I will use one rgb led rather than 3 separate ones.
I have a couple of protons on order, they are quicker and have more memory which might help.
Anyway way of moving the download loop to an if statement rather than a 'while' loop? Or maybe the data will have to be split into smaller chunks, sounds like a fudge though.
Once all up and running I was thinking of putting together a phonegap app to be able to send stuff to the printer. I'm going to play around with canvas / svg and see if I can export that in the correct format to send to the printer. Could possible use native iOS api to screen grab the image from a webview.
Anyway, thanks for you help on this. You should take a look at our company website wearemothership.com
maybe we can collaborate on a project some day.
James Adam <james...@gmail.com>: Jan 22 12:38PM
Hi again Stuart,
So there’s good news and bad news. The good news is that I have my spark core and SD card playing nicely. The bad news is that the sketch still doesn’t seem to reliably work. At the moment, I am not 100% sure why, but this comment, above the ‘loop()’ function in the spark ‘blink an LED’ demo sketch has been wondering:
"Make sure none of your code delays or blocks for too long (like more than 5 seconds), or weird things can happen.”
It’s pretty likely that downloading the printout is going to take more than 5 seconds, and that might explain some of the weird stuff that I’ve been seeing (connections waiting for data all the time, core no longer being flashable without a hard reset...). However, that’s clearly not the issue that you saw, and so I’m going to have to tinker a bit more to figure things out.
BTW, I tried to download your ‘TMP’ file, but Dropbox thinks it has been removed. I’m still happy to take a look, just let me know when it’s visible again.
Stuart Eaton <stu...@wearemothership.com>: Jan 22 06:42AM -0800
I totally rewired my circuit, used shorter jumper cables where possible and
ran some SD tests. I could write and read 200k files no problem. So I
continued to re-build the rest of the circuit.
I found the problem in the end, and i feel quite embarrassed!, I had not
been giving the printer enough volts. It was running off a separate 5.2v
usb charger. After giving it 9v it's printing the test pages fine :) I cant
print from URL or HTML though but at least the basics are working now.
Then I did something stupid and fried my Sparkcore! Aaaagh! Not quite sure
what happened but i think i gave it 9v that was supposed to be going to the
printer. Live and learn I suppose. Its a shame because I had managed to
package it all up in a box, was starting to to take shape.
When i get a new core I will let you know how I get on at the next stage.
Any ideas how I could still use one power supply 9v to drive the core and
printer? I really don't want to power supplies for this thing. I suppose i
need some voltage regulator to get from 9v to 5v.
Stuart Eaton <stu...@wearemothership.com>: Jan 22 06:51AM -0800
James Adam <james...@gmail.com>: Jan 22 02:56PM
Well done getting it working! If you can share your final sketch & wiring diagram I’ll see if it resolves any of the issues that I’ve had.
Regarding power, I’ve always used power supplies that are 5V and can supply at least 1.5A, and ideally 2A current. Interfacing this with the spark core is pretty simple — just connect it to the ‘VIN’ and ‘Ground’ pins on the core, and you won’t need USB power at all. You can see some example links to power supplies on the github wiki component page.
Again, well done - I’m looking forward to folding this into the main repository as a supported implementation :)
James Adam <james...@gmail.com>: Jan 22 02:58PM
> On 22 Jan 2015, at 14:56, James Adam <james...@gmail.com> wrote:
> Regarding power, I’ve always used power supplies that are 5V and can supply at least 1.5A, and ideally 2A current. Interfacing this with the spark core is pretty simple — just connect it to the ‘VIN’ and ‘Ground’ pins on the core, and you won’t need USB power at all. You can see some example links to power supplies on the github wiki component page.
Just to clarify - by powering your Spark Core using the ‘VIN’ & ‘Ground’ pins, you can also connect your printer to the same pins (or connections on the same breadboard rail). Hopefully that was already clear :)
Stuart Eaton <stu...@wearemothership.com>: Jan 22 07:14AM -0800
Yeh. I was originally doing exactly that but maybe I didn't have enough
amps! (it did print perfectly straight away with 9v).
As soon as I get some new cores I will try again with another power supply.
I have one which can do 5v at 3000mA
On Thursday, 22 January 2015 15:58:14 UTC+1, James Adam wrote:
Stuart Eaton <stu...@wearemothership.com>: Jan 22 08:59AM -0800
Here is my wiring. Probably looks a mess, not used Fritzing before.
On Thursday, 22 January 2015 15:56:07 UTC+1, James Adam wrote: