In SX Microcontrollers, SX/B Compiler and SX-Key Tool, tdg8934 wrote:

Just a little more info:

The cascaded LED drivers (MBI5024GF) that are on the Absen-OF20V 16x8 RGB module acts like cascaded '595 ICs with 16 outputs. In my previously attached SX28 code, you will see that I set /OE high initially (e.g. OE = 1), then after the data gets clocked, I set /OE low (e.g. OE = 0) all from the SX28 micro-controller. 

I also pulse out the Latch signal after the data is clocked out. 

The reason I am mentioning this is that I saw in some posted circuits on the web, that the design ties OE and Latch (ST) together and calls that the PWM signal as sent to the micro-controller (probably a PIC). 

Do I connect /OE to the Latch? Do I pulse out the tied together signals after the data gets clocked out? What does the SX28 do to these pins? Is the PWM command really going to go to the /OE line (or /OE and Latch lines)?

The problem I see with using /OE (with or without Latch), is that the 16x8 RGB module has ALL of the /OE lines on ALL of the cascaded MBI5024GF led drivers tied together. So this means that setting /OE high or low will affect ALL of the LED outputs not individual Red, Red2, Green, Blue LEDs to get 256 shades. Am I right about this?

There is no mention on any datasheet to say that the MBI5024GF has any PWM built in BUT the Absen-OF20V 16x8 RGB module (which has these cascaded MBI5024GF LED drivers) states in it's data sheet (previously attached) that the all the LEDs have 256 Greys which tells me that they are suposed to be able to do PWM "SOME HOW??" from the Absen-OF20V RGB modules with no PWM signal. 

Also these Absen-OF20V 16x8 RGB modules are used in huge outdoor LED display signs with full 36 bit color. This again infers that PWM must be possible. However, these modules are cascaded by the 100's to form these huge outdoor signs. They are normally controlled by a custom PCI card with Ethernet and DVI for video input.

I am trying to find a way to basically re-create something on a simpler scale that can be controlled by a Parallax SX28 micro-controller and not by this card because the PC software is not that good. It will be connected to a PC at sometime, probably via Serial or (USB-to-Serial) to send the data from a custom software program - maybe Visual Basic. Im sure I could even use Hyperterminal today but will need something more robust on the PC. But thats for later. [b]Todays question / concern is PWM possibility for individual RGB LED control using an SX chip with this Absen-OF20V 16x8 RGB modules - cascaded a few dozen times. 
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Is this still possible? I hope everyone can see my intentions. 

Thanks for listening and your assistance.

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