PICAXE-28X2 and AS1112 Led Drivers

Hello mates,
I'm doing a project with PICAXE 28X2 to control AS1112 LED drivers by SPI. Schematic is with Daisy chain 3 drivers. So, I need one more CLK for Grayscale mode. I tried to use pwm instead that CLK, but it not working. I can not shift data in and program. Could you give me some help about that? I attach AS1112 data sheet.

Welcome to the PICAXE forum.

What PWM frequency and duty cycle are you using.
Have you determined that the timing is as per the requirement of pages 14 and 15 from the datasheet.

It would be helpful iof you posted:
- your program code developed so far and
- your schematic diagram, which may also be useful

Thank you for your fast reply.
My scheme is a variation of Barry Scott matrix led cube from this forum. My project is with 4x4x4 RGB Prianha common annode LED. I choose AS1112B, because they have great options, but also a big minus - QFN pack (5x5mm chip) and special solder technique. So I attach now my schemes and just a basic test program - everything what I did up to now. I haven´t experience with SPI and PWM and accept all advices.

Here is my test code.

Does some mate to help me?

Have patience LEDMAte mate

People will have to read and absorb the data sheet to work it out for you.
Then people will have to look at your schematic.
Remember, this is a volunteer Forum.

If you wish to pay then I'm sure people will do it very rapidly
(I'm joking , people here are very altruistic).

This seems quite an advanced project, and especially without experience of SPI or PWM.

I would suggest starting with a smaller project which just controls one AS1112 and get that working before moving on to a much more complicated project.

Thank you guys! Of course I don't want to push anybody or to make somebody stressful or unhappy! I understand very well that is a forum! So I'm trying now just to program one of AS1112B. If I have some success I'll share immediately.

So, guys, I have read very carefully few times AS 1112 data sheet and experiment a lot with PWM. I thing main problem is how to configure Greyscale clock using PWM? AS1112 manufacture support said me is opportunity to do it. According to data sheet I need 4096 pulses per period, and with "pwmout" is possible just max 1023 per period. I tried with "for-next" loop, but it's not going. Just different LED's start to light, not those have to...

Have you tried the pwmout wizard in the program editor?

PICAXE > Wizards > pwmout

I tried...

Hi LEDmate,

the AS1112 greyscale CLK seems pretty similar to greyscale CLK setting of TLC5940.
So, it may help you to have a look at the following thread.. http://www.picaxeforum.co.uk/showthread.php?t=8616&page=3

Most likely, you can use an Picaxe 8M loaded with the GSCLK.bas provided by Gbrusseau, to clock the AS1112.
Hope it helps!

Thank you mate! It's very helpful! I'll try this as soon is possible!

I found out a problem with soldering of those little chips QFN AS1112. I made a short circuit between legs and ground base... Soldering of RGB LED matrix was like beach walk compare with this... So, I decided to change my project using NT (DIL)TLC5940 by TI. Of course I'm over my budget, but is better to finish the project... Thank you very much to everybody who helped me!