Arduino

From: ANT_THOMAS27 Jan 2015 22:27
To: koswix 258 of 542
Whilst you have to order a minimum of 5 them prices are actually fairly reasonable.
From: ANT_THOMAS27 Jan 2015 22:32
To: Chris (CHRISSS) 259 of 542
I'm using the ShiftPWM library and they seem to work really nicely.

Any flickering has totally gone now I'm using the shift registers. Still figuring out how to use 2 daisy chained together properly.

I was easily able to convert my existing sketch to make use of the shift registers.

rather than:

analogWrite(ledPin1,255);

it is just:

ShiftPWM.SetOne(1, 255);

with the 1 being pin 1 on the shift register. Then you just cycle/loop like any other PWM loop example.
From: koswix27 Jan 2015 22:32
To: ANT_THOMAS 260 of 542
Think he said he paid £10 for ten boards. Pretty small boards, but still.
From: ANT_THOMAS27 Jan 2015 22:39
To: koswix 261 of 542
It looks like about 70 USD for 5 15x20cm boards which is fairly reasonable.

I probably won't need a board that size once I actually draw out the circuits properly.
From: koswix27 Jan 2015 23:10
To: ANT_THOMAS 262 of 542
I've been trying to get my head round Eagle CAD (Jim lent me a copy of the pro version). Takes some getting used to, but a few youtube videos definitely helped.

I'm going to give the laser transfer/etching method a go once I've finished designing the board. The board's not very complicated, just a bunch of floppy drive sockets routed to a pin header to make my floppy organ (it's cold outside, John) a bit more organised and less prone to random braking.
From: ANT_THOMAS27 Jan 2015 23:15
To: koswix 263 of 542
I think if I design mine well and I don't just have the screw connectors down one side, instead having them spread across 2 or 3 sides I could probably get it down to 10cm x 10cm which is only $18.90 for 5. Assuming that leaves enough space for 20 to 24 transistors.
From: ANT_THOMAS27 Jan 2015 23:23
To: ALL264 of 542
There we go, very simple test.

4 LEDs addressed from one shift register, 4 LEDs addressed from the other.

From: Chris (CHRISSS)27 Jan 2015 23:45
To: ANT_THOMAS 265 of 542
I wonder of that will work with the PWM frequency library.

Is it the power supply (if you're using it) that has fixed the flickering?
From: Chris (CHRISSS)27 Jan 2015 23:46
To: koswix 266 of 542
:) Can you make it play a song?
From: Chris (CHRISSS)27 Jan 2015 23:47
To: koswix 267 of 542
Nooo. Really no. Don't make me want to spend even more money designing my own PCBs as well. Yes, I'd love to. I've already spent too much. Lots of little spends adds up.

Do all 5/10/whatever boards need to be the same?
From: ANT_THOMAS27 Jan 2015 23:59
To: Chris (CHRISSS) 268 of 542
ShiftPWM allows you to choose the PWM frequency so the other library isn't needed.

It seems anything over "75" stops any flickering. I had it at 150.

I'll try 3 shift registers tomorrow.
From: koswix28 Jan 2015 00:20
To: Chris (CHRISSS) 269 of 542
Currently yes, but I'd have to hand code it and I think I'd go insane. Next job is improving the software. A lot.
From: Chris (CHRISSS)28 Jan 2015 01:08
To: koswix 270 of 542
I can wait til the software is better. Can you play the theme from Project X on the Amiga?
From: Chris (CHRISSS)28 Jan 2015 01:14
To: ANT_THOMAS 271 of 542
Aha. Handy. Is 150Hz enough with them dimmed? Think it's more noticeable in a dark room too. Lots of useful libraries for the Arduino.

I'm still waiting for my two Nanos. I have a USBASP programmer which I'll use with my Pro Mini for now. Also waiting for a FTDI adapter which will be an easier connection than the USBASP. Gonna have a play with the nRF24L01 transceivers. Did you add a capacitor to the power connections on yours?
From: Chris (CHRISSS)28 Jan 2015 01:21
To: koswix 272 of 542
I asked on the Arduino forums about the bits in that LED controller. They are FETs and rated at 2.8A. Must be heat dissipating pads.
From: koswix28 Jan 2015 09:15
To: Chris (CHRISSS) 273 of 542
If you give me a midi file of it.
From: Chris (CHRISSS)28 Jan 2015 09:57
To: koswix 274 of 542
I will try and find one and give it to you (YJ)

I wired up my LED strip the other night using a BC547. I'm sure I had it connected right but the LEDs didn't respond to the PWM unless I swapped the transistor around the other way. Any ideas if my circuit is correct?
From: ANT_THOMAS28 Jan 2015 11:29
To: Chris (CHRISSS) 275 of 542
Different transistors definitely have different pinouts in case you looked at a generic schematic.
 
From: Chris (CHRISSS)28 Jan 2015 11:45
To: ANT_THOMAS 276 of 542
I got the pin layout from the eBay listing so it should be right. And I used the same ones with my clock with no problems.
From: koswix28 Jan 2015 12:30
To: Chris (CHRISSS) 277 of 542
I'll confess to not really knowing anything about transistors.