Comments on: How to drive USB keyboard from Arduino

By: oleg

oleg — Wed, 03 Mar 2010 02:08:32 +0000

I tried multimedia keys on my cheap HP keyboard and they didn’t work in boot protocol mode. Most likely, you would need to do HID report parsing. Read Richard’s game controller articles to get an idea how to do it.

By: rgm

rgm — Wed, 03 Mar 2010 01:57:43 +0000

Is it possible to read the state of “multimedia” keys if the USB keyboard is in boot protocol mode? My keyboard, a cheap Dynex DX-WKBD, has several “extra” keys that I would like to use.

By: oleg

oleg — Fri, 30 Oct 2009 13:59:38 +0000

Richard,

I agree. In fact, that’s exactly my plan in case Maxim stops producing MAX3421E – build a SIE out of PIC24, implement everything up to transfers in PIC firmware and slightly modify usb library. But frankly, I doubt MAX3421E will disappear any time soon; I think they just need an excuse for not supporting it.

BTW, thank you for sharing your code – I learned a couple of things!

Oleg.

By: Richard

Richard — Fri, 30 Oct 2009 13:46:42 +0000

IF the MAX3421E is discontinued it will be sad because it is a great entry level USB host device and great for use with Arduino. Samples still seem to be available, worth getting some spares !

The good news is that even if this device is discontinued, then it is unlikely that the resources you spend will be wasted. USB generally and the MAX3421 device provide a strongly layered architecture, and the lower hardware layers are suprisingly easy to replace. Most of the low level drivers ara already done, so the part you develop will likely work on other hardware with minor adaption. The emergence of USB host controllers within microcontrollers (AVR32, PIC32) will give us plenty of future alternatives.

By: oleg

oleg — Tue, 27 Oct 2009 22:26:53 +0000

dkb,

Where did you get this “end of this year” idea from? I e-mailed Maxim today about end of life of MAX3421E and got the following reply “No final discontinuance date set as yet for this product, but it is Not Recommended for New Designs”, which, according to their policy http://www.maxim-ic.com/company/policy/product_discontinuance_policy.pdf , would give us at least 6 months to leave if Maxim announces discontinuance tomorrow. Design of the next version of the shield is in progress, it can be finished very quickly if needs be. The compatibility will be maintained on the library level – if your app calls USB class functions, it will continue working.

By: dkb

dkb — Tue, 27 Oct 2009 04:36:45 +0000

My point is that after the end of this year there will not be a MAX3421 in production and there is no replacement so is there a plan for what to use for the USB Host Shield instead? I’d hate to spend resources writing drivers for a device whose near future is uncertain.

By: oleg

oleg — Tue, 27 Oct 2009 02:10:40 +0000

What is your point?

By: dkb

dkb — Tue, 27 Oct 2009 02:04:01 +0000

For what its worth I contacted Maxim since the 3421E is not recommended for new designs and got this reply:
| There is no replacement or upgrade recommended for the MAX3421.
| No other company is known to 2nd source this device.

By: oleg

oleg — Sun, 25 Oct 2009 00:40:12 +0000

If you are talking about this shield ->http://www.arduino.cc/en/Main/ArduinoEthernetShield , it uses SPI also. SCK, MOSI and MISO can be shared between two shields, SS on USB Host shield is routed via a jumper, it can be re-routed on any unused pin, if necessary.

By: dkb

dkb — Sun, 25 Oct 2009 00:27:43 +0000

It looks like you are requiring pin 13 for SPI to communicate to the shield. What options are there if you want to use the USB Host shield with an ethernet shield which needs dedicated access to digital pin 13?