PropLilly worlds smallest Demoboard

tonyp12

At 39mm by 22mm but still with "all" the features of the Prop demo board.

p0 to p7 pin headers (upper right) and a 3pin 5v (400mA), 3.4v (120mA) and Gnd

Left pin headers, dual sigma adc, one dac, video, vga and dual h-bridge.
and another set of 5v 3.4v and Gnd

Goodbye Ftdi and hello Silabs Si2110
It's a hid uart and don't need a driver, until prop-tool support it natively you need use the virtual com port.
I made GPIO9 the DTR (as open drain), so lets make that the official pin for that.

The cp2110 puts out a 6mhz clk, so no need for a crystal while plugged in to a usb port.
If running of a micro-usb charger, remove lower jumper and insert radial crystal.
I asked Silabs to have an option to always have the clk running even if not enumerated and they will look in to it.

Lower left is the 0.4 amp (5V) for two bi-directional dc motors or a single stepper.

P.S this prototype was hand pasted (syringe) and hand pick-and-place (0603), just need a steady hand.
video of propLilly in action:
http://youtu.be/G2yk0gnwKEE

mindrobots

That is an amazing piece of work! There should be room for that inside most anything!

Cluso99

I agree, its amazing. Smaller that the VGA connector itself!

turbosupra

Awesome!

I'd like to read more about the ftdi chip replacement, it'd be nice to be able to produce a pcb without adding the $15 cost for the ftdi usb adapter.

jmg

Small is always good. OP likely meant CP2110 (not Si2110) -

I think I've seen that the Silabs parts DO need the ESD devices they show on most schematics. Are those on this Board ?

Q: Can you control the clock output on the CP2110 via the HID, and how much does that move around as USB sends and idles and is unplugged ?

If the CLK is not there, when not-enumerated, that means this cannot work stand-alone ?

Given these Silabs USB Bridge parts are OTP uC, I've often thought they should publish the code, and allow simple changes like that CLK on POR.

tonyp12

SiLabs recommends the littlefuse, no room on this board and pretty expensive
see the picture below were I do use in on CP2112

You can set the clk to anything between 24mhz down to khz.
but it's burn once, you can not change it back.

You can use this board standalone if you remove the lower jumper and insert a 5-6mhz cylinder crystal instead.
http://www.mouser.com/ProductDetail/Citizen/CSA309-6000MABJ-UB/?qs=sGAEpiMZZMsBj6bBr9Q9aQX%2fBWSXR5XrQKmhWEJMjEc%3d

But if we could get SiLabs to change their firmware to have the option to have clock always-on as most usb chargers don't enumerate.
I was thinking about a trick of having the prop in rcfast mode and vga sending a fake enumerate sequence from p0-p1 pins to the D+/D- lines.

tonyp12

This is the setid software to set pin gio, but it's burn settings once in each catagory so be careful.
Rx is not changable, so not listed.

Circuitsoft

You can set an FT232RQ to have a clock out, and 6Mhz is an option, and the chip itself is plenty cheap.

Tubular

Nice work Tony. You even found room for some mounting holes...

tonyp12

>You can set an FT232RQ

Does it have a 3.4v at 120mA regulator that other IC can share?
Enumerate to request that the USB host release (up to) 500mA
A hid device with no drivers (dll) to install, as with some corporate laptops that could be a no no.
The DTR (a gpio) can be programmed as open drain, so no more weird reset issues or need for a external transistor on the line.
Maybe can get clk always-on as it's just a firmware fix.

CP2110 is the future

Circuitsoft

FT232R offers 50ma from the 3v3out pin. In the past, I've had a heck of a time trying to get SiLabs-based devices working at all, so I'm pretty well set against them.

richaj45

Hello:

How about using the center of a Parallax demo board. It does not have the serial connection but it is pretty small once it is cut out of the main board. Maybe Parallax will sell the board with out all the other stuff on it for cheaper.

rich