Multiple Usb Host Shields?

Using Arduino Networking, Protocols, and Devices
1

hello, I've been wondering if it is possible to connect two (or more) Usb Host Shields to a single microcontroller.

My understanding is that the Usb Host Shields are just spi devices that can connect via the spi bus. Thus, it would be possible and one would only need to assign a different SS pin for each device.

The problem is that the library I'm using assumes only ONE Usb Host Shield. I'm sure if I were to connect another Usb Host Shield, it would require modifying the library a bit as things would conflict.

I would like to use two USB Host Shields for Arduino Pro Mini connected to a single Teensy 3.2. So far, I have one connected and it works fine. Would it be possible to connect a second one?

fyi, I'm trying to connect both a usb keyboard AND a usb barcode scanner to the teensy. I know both can be individually connected (one at a time) but I'm trying to figure out how to do both at the same time. This is an example of a usb keyboard (the barcode scanner example is almost identical). Would it really be as simple as just declaring another Usb object?

Any help greatly appreciated. Thanks.

2

It probably would be fine. You could maybe skip modifying the library and just writing the seperate SS pins to turn each shield on and off. Then you could monitor one and then the other.

3

Almost all the code dealing with spi is in the library, so it would be hard to not modify it. I guess I could choose a separate SS pin and just control it individually by writing it low and high, but I would still need to manually control the slave device by myself since I'm letting the other shield use the library.

I feel it's as if I need two instances of the same library. One for each slave device.

4

Hi there!
Have you solved this? were you able to have the two USB shields working?

5

i see its been a while since someone replied or asked the same question but its worth a try to ask again.

i had the same idea to use 2 USB Host shield to attach 2 scanners, instead of using 2 Arduinos.
were you guys able to accomplish this task?