Moitessier hat questions

JumbleDuck

JumbleDuck

Well-Known Member
Joined
8 Aug 2013
Messages
24,165
Location
SW Scotland
Visit site
My crew is thinking of buying a Moitessier hat for a Raspberry Pi, but has a couple of questions to resolve before investing rather a lot of pocket money. Can anybody help ...

Does it fit in a standard PI case?

Does it still allow use of GPIO pins for a touchscreen interface?
 
JumbleDuck said:
My crew is thinking of buying a Moitessier hat for a Raspberry Pi, but has a couple of questions to resolve before investing rather a lot of pocket money. Can anybody help ...

Does it fit in a standard PI case?

Does it still allow use of GPIO pins for a touchscreen interface?
Click to expand...
Only had a quick look, but I would guess you would need a modified case. Doesn't look as though it duplicates the GPIO pins.
 
pessimist said:
Only had a quick look, but I would guess you would need a modified case. Doesn't look as though it duplicates the GPIO pins.
Click to expand...
Thanks. Modifiying a case wouldn't be a problem as long as it physically fits in one. The pictures seem to show some GPIO pins making it through, but we can't make out which.
 
I have one here ... a Mk2, It has no sockets on the top surface, so no GPIO pins will be passed through. The pins shown standing up are a 6 pin header, I assume for JTAG access to program the uProcessor on board with its bootloader. I have a Mk1 somewhere ...
 
What does it do? It seems to add gps and ais to a Raspberry Pi with added barometer etc. Is the idea that you don't need anything extra for navigation except a screen?
 
rszemeti said:
I have one here ... a Mk2, It has no sockets on the top surface, so no GPIO pins will be passed through. The pins shown standing up are a 6 pin header, I assume for JTAG access to program the uProcessor on board with its bootloader. I have a Mk1 somewhere ...
Click to expand...
Thanks - that's very helpful. The touchscreen currently in use uses the second and thirds pairs of GPIO pins at the end opposite the USB ports. Would there still be access to those with the Moitessier hat in place? And di you know what the pins marked I2C on teh hat are for?

Apologies for bombarding you with questions.
 
I suppose you could always put something under the hat (a head maybe?) to get the pins out first?

I read this wondering what was so special about Moitessiers hat and was disappointed. To that end I have scoured the net and discovered that he very rarely wore a hat. The only pic I could find appeared to be one of those Breton jobbies.
 
JumbleDuck said:
The touchscreen currently in use uses the second and thirds pairs of GPIO pins at the end opposite the USB ports. Would there still be access to those with the Moitessier hat in place? And di you know what the pins marked I2C on teh hat are for?
Click to expand...
Warning - I am a Raspberry Pi novice but ...
Those pins are Ground, 5V and the I2C interface. Several touchscreens use that interface. Multiple devices can be attached to an I2C interface. They each have a unique address so they don't interfere.

The Tech Spec page 5, Fig 4 shows how the GPIO is used. It looks like you can share the I2C as suggested by JBJag27 or with the I2C option for the hat.
 
JumbleDuck said:
Thanks - that's very helpful. The touchscreen currently in use uses the second and thirds pairs of GPIO pins at the end opposite the USB ports. Would there still be access to those with the Moitessier hat in place? And di you know what the pins marked I2C on teh hat are for?
Click to expand...

The Moitessier Hat has a full socket, so no pins are accessible, you'd need to put a breakout hat on the pi first to pick up any other pins, and then plug the Moitessier in on top of that.

I2C is an interface bus, many things use it, it is adressable, so you can have multiple devices hanging on the bus and each one can be spoken to by its addess on the bus. The 6 pins marked I2C on the moitessier are not populated on my board, you'd have to find a small header and solder it on if you wanted to pick them up, I suspect the duplicate the I2C bus on the Pi.
 
Thanks very much everyone. I gather that the connections to the GPIO pins are for power, ground and the touchscreen via I2C, I've had a look at the Moitessier hat technical manual with two pictures of the top surface, one of which shows pin connectors labelled I2C and the other of which shows unpopulated contact points, as reported by rszemeti.
 
You must log in or register to reply here.

Share this page

Top