SparkFun Forums

[radialhat]

Hello sparkfun community,
I got a question that I also just posted up on Reddit
Imagine this scenario, a restaurant, 5 tables, each table with some sort of 555 timer based device coupled with an RF transmitter and 2 physical buttons, one that calls the waiter and the other that asks for the bill, and an arduino with a receiver module that will receive communication and know which table had pressed which button and transform this into a beep on a computer alongside a label on the screen with the table number... Is this acomplishable? What do I need to have in mind?

[stevech]

first: power source.
what's the 555 purpose?

I'd do this with XBee S1 in a proper package. No microprocessor needed.
XBee's MAC address reveals table # (MAC implies table # as we know where we put the XBees)
Two DIO bits on XBee for push buttons (with some debounce)

Receiving end is another XBee S1 with USB/Serial link to RPi or PC or whatever displays the button pushes.

Quite simple.
Send me a zillion dollars and I'll do it!

[Mee_n_Mac]

Too late ...
http://www.wsj.com/articles/SB100014240 ... 3174389816

Great thing about the Ziosk at Applebee's ... there's a refill my drink button !!

[Ross Robotics]

Yep, a lot of restaurants have these now.. Well, all the high end restaurants. You can make something more simple and cost effective for "family owned" restaurants..

I agree with Steve. Make as simple as possible, which would make it inexpensive..

[lyndon]

It's certainly possible, but I would just use cheap Android tablets at each table (chained to the table!) and a PC running a webserver at the host station. PC could even be a Raspberry Pi!

I'm positive that the lifetime cost of my solution would be lower. I could deliver that solution in a weekend. Wanna pull the trigger on it?

[edit] And I posted that before I read 'Mac's link.

[Ross Robotics]

Cheap tablets? I haven't seen any under $100.. That's not cheap. This concept is what places like Applebee's use. But they're in large, bulky enclosures.

As for the long term, how many tablets will break in a week? A month? People are destructive animals.. Especially a 2 yr old!

[lyndon]

Lots of tablets under $60. All it needs is wifi and a browser. Can likely get even better pricing if you buy in quantity direct from China via Alibaba.

Cheap tablets? I haven't seen any under $100.. That's not cheap. This concept is what places like Applebee's use. But they're in large, bulky enclosures.

As for the long term, how many tablets will break in a week? A month? People are destructive animals.. Especially a 2 yr old!

[Ross Robotics]

I stand corrected. $60 @ 10 tables is $600.. And I hope a restaurant has more than 10 tables..

[lyndon]

Can the receiver access the transmitter's MAC address?
I should know this: I have a couple of those things still in the package...

first: power source.
what's the 555 purpose?

I'd do this with XBee S1 in a proper package. No microprocessor needed.
XBee's MAC address reveals table # (MAC implies table # as we know where we put the XBees)
Two DIO bits on XBee for push buttons (with some debounce)

Receiving end is another XBee S1 with USB/Serial link to RPi or PC or whatever displays the button pushes.

Quite simple.
Send me a zillion dollars and I'll do it!

[Mee_n_Mac]

Can the receiver access the transmitter's MAC address?
I should know this: I have a couple of those things still in the package...

first: power source.
what's the 555 purpose?

I'd do this with XBee S1 in a proper package. No microprocessor needed.
XBee's MAC address reveals table # (MAC implies table # as we know where we put the XBees)
Two DIO bits on XBee for push buttons (with some debounce)

Receiving end is another XBee S1 with USB/Serial link to RPi or PC or whatever displays the button pushes.

Quite simple.
Send me a zillion dollars and I'll do it!

And if not aren't there 6 more DIO pins that could be wired to ID up to 64 tables ?

Even better might be to use the PT2262/2272 encoder/decoder set and a cheapo AM Tx/Rx like Adafruit does in their key fobs.

[lyndon]

Reason for the question was I wondered if the transmitter could be done without a microcontroller. I do like that keyfob idea.

Anyway, after taking a quick look on Alibaba and finding WiFi Android tablets for $35 each (qty 10), I'd still consider the tablet approach first. With stuff like this, scope creep tends to happen really quickly.

[radialhat]

Hello everyone,
Thank you for the answers, while the tablet approach seems nice its costly and a bit out of what I have in mind.
Loved Mac's and stevech's suggestions... had few time to come back here due to being working on the restaurant
(building stage) but I'll have to take a moment to study stevech's idea and mac's which seem to be more complex
Regards
Radialhat

[Mee_n_Mac]

Here's the Adafruit 4 way fob. The important point is that it uses the aforementioned encoder/decoder sets to ID and "marry" fobs and receivers. Using cheap and "long" range Tx/Rx sets to carry the info.
http://www.adafruit.com/products/1095

[stevech]

Reason for the question was I wondered if the transmitter could be done without a microcontroller.

see 2nd post


On using Tablets at restaurant table...
Bring on the toddlers!

[lyndon]

I know that the xbees can transmit to each other without needing a microcontroller. What I don't know is if the PC at the receiving end can get access to the MAC address of the transmitter.

Reason for the question was I wondered if the transmitter could be done without a microcontroller.

see 2nd post


On using Tablets at restaurant table...
Bring on the toddlers!