Hi all, absolute noob here, so please be gentle 
I have been having a bit of fun playing around with a 7219 chip and an 8*8 matrix. I've succeded in wiring everything up correctly and it all seems to work, but the characters are displayed wrong way round, like when you look at it in the mirror. Not sure what I've done wrong, so any help appreciated. I've tried a couple of different sketches, both with same result, so no idea what to do next. On of the sketches is from here Tutorial – Arduino and the MAX7219 LED Display Driver IC | tronixstuff.com.
Regards
Luigi
Before someone else tells you tells you and also your circuit schematic 
Try swapping the Anode pins, or the digit pins, end for end.
I'm pretty sure the wiring is correct, when I try the example included with Ledcontrol library, the letters spelling out Arduino are displayed correctly, so I'm certain that it must be a coding error. Another possibility is that the 7219 chips I have maybe dodgy?
Pedro147:
Before someone else tells you tells you and also your circuit schematic
I did post a link to schematic and code, didn't think it would have been a good idea to post the code directly in my post as it does seem to be quite long :~
Another thing I hadn't thought of, would using a matrix with common anode as the one I'm using now make a difference? I think the one the guy is using in his examples is common cathode.
luigione:
I'm pretty sure the wiring is correct, when I try the example included with Ledcontrol library, the letters spelling out Arduino are displayed correctly, so I'm certain that it must be a coding error.
In a sense, it will in fact be a coding "error", but the problem is that - as with many other things here - there is not necessarily a "standard" way to wire up displays, so the wiring diagram on that page
does not for a start, correspond to the module from eBay (it is actually for the alternate polarity version of the matrix), and I do not know whether it matches the other module shown either. In fact, there are already two variants of the eBay module with pins swapped on the interface connections on the ends but the same connections between MAX7219 and display. The eBay one is an annoying module as it cannot be directly "chained" as can the other shown - you need flying wires..
And the diagram of the display connections is wrong! Those used on the readily available modules are arranged quite differently.
luigione:
Another possibility is that the 7219 chips I have maybe dodgy?
Forget it. If it is displaying, it is working - there is no malfunction of the chip that can merely display in reverse.
luigione:
I did post a link to schematic and code, didn't think it would have been a good idea to post the code directly in my post as it does seem to be quite long
You are probably right about that. As long as you have cut and pasted that code from the website - and it works - we can be reasonably happy you have not accidentally inserted something to cause the trouble.
On analysis, I gather that you have followed the diagram and it has the column connections connected in the reverse order to what the code (which presumably matches the ready-made modules) expects. You will need to swap pins 5 and 9, 2 and 14, 7 and 8, 1 and 12 on the matrix display (not the MAX7219).
Yep , does seem that the pins are inverted, been having a bit of fun trying to figure them out, nearly there, but with your help it will be even quicker.
Cheers 
Yep, works a charm now, cheers fellas.
I've ordered a few of the kits on ebay, the type with the pcb. I'm sure they'll be easier to work with.
Now off to play with the 7 segment displays :-), managed to get myself a couple of the Arduino starter kits from ebay for about £26, so plenty of toys to play with.