Neopixel on spi189 @ 7,5MHz?

Hardware
1

In a previous project I controlled a Neopixel LED array with spi257 @ 7.5MHz which worked fine (using IMP002)
In my current project spi257 was already taken so I took spi189 @ 7.5MHz to also here control a Neopixel array (also using IMP002)
Controlling the Neopixel kept on failing until I had a look at the https://electricimp.com/docs/api/hardware/spi/configure/
page and noticed the difference in possible data rates for spi257 and spi189: the range for spi189 being half of that of spi257. With more luck than knowledge I tried the setting for spi189 (3750) aligned with that for spi257 (7500) … and it worked!?

Can anyone explain and/or does anyone control Neopixel with spi189 on 7.5MHz successfully?

2

All of the SPI buses can be configured to run at 7.5MHz - so you shouldn’t have any issues.

Make sure you hook up SPI189’s MOSI pin (pin 8) to Data In on the NeoPixels. Here’s some sample code I just tested using SPI189:

`#require “WS2812.class.nut:2.0.1”

// Create the Pixel Array
pixels <- WS2812(hardware.spi189, 5, false);
// Auto-configure the SPI-bus
pixels.configure();

// Set pixel buffer to purple, then draw/output to pixels
pixels.fill([100,0,100], 0, 4).draw();
`