Connecting a USB keyboard to a propeller chip

mdavey

Is there anyway to connect a USB output keyboard to a propeller chip? I have tried using a USB to PS2 converter but it doesn't work, at least not with the converter I have. I know the program and port work fine because I can connect it to a PS2 style keyboard and it works. I want to do this so that I can use a particular keyboard I have and it is only USB. Mike

Rayman

It looks like the Viniculum chip can be programmed to host USB devices. But, the only firmware I see is to host flash drives... So, I guess you'd have to program the Viniculum yourself...

I think the Maxim 3421E could do it also.· It has built-in host code too, but I can't tell what it can actually host.· Probably have to program this yourself too...

Post Edited (Rayman) : 12/21/2007 7:22:14 PM GMT

Paul Baker

The vinculum cannot be programmed by third parties, we asked to get a hold of thier SDK toolchain for the Vinculum and they politely declined (something about too many tricks used to fit it in the current version of the chip and they don't have the resources to explain what they did). There is a HID driver class for the vinculum, but there were outstanding issues with the first release of the driver. I don't know if a subsequent revision has been released.

Honestly the easiest way to go is to just buy a PS/2 compatible keyboard, you will spend considerably more money trying to interface with your USB keyboard than just getting a new keyboard.

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Paul Baker
Propeller Applications Engineer

Parallax, Inc.

Post Edited (Paul Baker (Parallax)) : 12/21/2007 7:19:24 PM GMT

deSilva

Paul Baker (Parallax) said...
.... something about too many tricks used to fit it in the current version of the chip and they don't have the resources to explain what they did...

That sounds a bell...

mdavey

Thanks for the feedback, it was about what I expected. I do still wonder why it doesn't work. From the view of the device that it is plugged into, what is the difference between a PS2 keyboard and a USB keyboard with a PS2 adapter on it.

Rayman

As I understand it (possibly wrongly) the mice or keyboards that go both ways actually implement 2 interfaces;· USB and the basically serial interface of PS/2 keyboard and mouse.· I don't know for sure, but there are 2 unused pins on the PS2 connector that must be used by the USB interface...· The one you have probably just implements the USB interface for simplicity...

Forrest

I'll add my 2 cents - those keyboard USB to PS/2 adapters do NOT work with all keyboards. They're specific to certain keyboards that were designed to function as USB or PS/2 keyboards.