Suggestions for Prop Shield V2

[hubbe]

I've been working with the prop shield to build a lightsaber, and I love it. (Details here)
However, there are a two quirks that I've had to work around, which would be awesome to address in upcoming revisions:

1) The serial flash is nice, but too small. An sdcard slot would be better I think. (Both would be best of course.) If you add a sdcard slot, consider making pin 4 the chip select so it's directly compatible with the Wiz820+SD adapter. Also, please make the sdcard slot stick out in the same direction as the usb connector. Having it go in the other direction makes it difficult to access in many situations. (Which is why I'm not using the Wiz820+SD adapter.)

2) The LED level shifters would be lovely to use, but I can't because I'm using WS2811 leds, and I'm using a modified version of the OctoWS2811 library to drive them. By doing it this way, I don't have to block interrupts or share time on the SPI bus, but it also means I can't use the builtin level shifters. It would be lovely if there were some pads to let you hook up the level shifters to alternate pins. (In my case pin 20) It would be even better if this was somehow configurable at runtime, but that seems like it would be difficult without using up more pins.

[Pensive]

1) The serial flash is nice, but too small. An sdcard slot would be better I think.

Isn't that drifting too far toward the audio board?

[Ben]

Maybe this helps with your immediate problem with not enough space in the serial flash: Forum Member Frank B maintains this lib: https://github.com/FrankBoesing/Ardu...ensy-Codec-lib

[PaulStoffregen]

Not sure how we could fit a SD card on there....

[MichaelMeissner]

Well, in theory you could mount the current prop shield under the Teensy, and mount this on top of the Teensy: https://www.tindie.com/products/Fusi...ll_prod_search

This card uses pin 10 for the CS pin, and standard 11-13 for MOSI/MISO/CLK. The prop shield doesn't use pin 10 as a CS pin, and pin 2 which is an alternate to pin 10 for the special CS pins is used as an i2c interrupt, and not a CS pin. So, in theory, you should be able to use the SD card along with the prop shield. However, I have not tried it myself, nor do I currently own the SD card shield.

[MichaelMeissner]

Isn't that drifting too far toward the audio board?

Though for something like a light saber, the width of the audio shield might be a problem.

[Constantin]

One option re: SDHC is the PJS008 from Yamaichi. It's through-hole (so it can be added by a user later on), relatively tiny (SHDC card size), and vertical (taking up little PCB space). The only downside to this component is that Digikey doesn't carry it, so I order them in bulk from Mouser.

[Pensive]

Though for something like a light saber, the width of the audio shield might be a problem.

Can one not stack the prop shield and the wizio SD adapter on top of each other? It's possible you might go too high then though....it's also a bit wider...

http://www.pjrc.com/store/wiz820_sd_adaptor.html

Or just get old school and run wires instead of stacking, with the old SD adapter?
http://www.pjrc.com/store/sd_adaptor.html

[hubbe]

I'm actually stacking the old SD adapter, it only needs three wires to make it work, but three PCBs stacked on top of each other is getting fairly big for what I'm trying to do.

[hubbe]

Not sure how we could fit a SD card on there....

I would get rid of the flash serial chip, the screw holes, and some of the useless headers near "Audio In". Then I'd move the audio output from the left to the right side, and remove the GND/5v from the left side since they are also present on the right side. With a little luck there would then be enough for a microsd slot on the left side. Having the sd slot on the same side as the usb port makes for easier access in certain types of devices.

[hubbe]

In case anybody is interested, I've actually made my own prop-like shield: http://fredrik.hubbe.net/lightsaber/v2/
Right now I have a few for sale here: https://www.fx-sabers.com/forum/index.php?topic=51903.0
Unfortunately I don't have the volume and experience that Paul does, so they are a fair amount more expensive.