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More programmable IO's


#1

Hello,

Is there already a component through wich i can get more IO’s on any board? I know you have boards with 60 IO’s, but thats not enough for a project i want to realize :slight_smile:

Its leading to the direction to replace a sps where the application is not that time critical.

Chooseable for this i need extensions for analog and digital io’s for signals.

Something like can-extention or uext extention…

Does something like that exist, or are you planning to implement something like this to your products?

best regards,
Trider


#2

How many is “more” :slight_smile:

60 is not enough ? How about 2 FEZ boards communication over a bus with 60 each giving you 120 ?


#3

Is this what you need?
http://www.tinyclr.com/hardware/1/fez-domino/#/grid/item/129/


#4

Can i access than from 1 fez board to the IO’s of the second one?

Well we talk about 100 IO’s. Is this solution endless expandable? And what do you mean with bus system? the Uext or can?

OK so digital IO’s can get realized by this solutuion (in case needed by reducing the voltage). What about the analog IO’s on the board? I haven’t found any documentation what they can. The range of voltage and ampere they can handle. Because 40% of the IO’s i need are analog… and the biggest board has 8 of them. and combining 5 of them to get the amount of needed analog IO’s is extrem expensive and now cost efficient. (i could use than the mini but still 5 times about 50 euro for 1 board)…

best regards
Trider


#5

I saw them already, but a question came up by these IO’s.

This looks nice, but what for IO’s are these? Analog or Digital? And wich Voltage and ampere they can handle?

best regards,
Trider


#6

Instead of giving you wrong answers…tel us more about what you are trying to accomplish and we will tell you what you need to make it work :wink:

IO40 board is all digital and can be chained to up to 320 IOs! We use quite few on our arcade game. See this video http://www.youtube.com/watch?v=uW3Lkw8TDE0


#7

My Project is for industrial usage.

I get a set of analog signals. 1 set has 2 - 4 analog signals to read. My Project is flexible from 2 Sets up to 8 Sets. These values are positions of some motors measured my a wire which gives me analog signals. Than because there is hydraulic, i get the current preasure of the hydraulic also as analog. Than i also need digital IO’s so i can see if a motor has reached his limit up or down. It is for lifting cars and bigger vehicils. All Motors need to accellerate the same and need to be on the same height. This must be regulated very carefully.

So all about, there are about 40 analog IO’s and 30 digital IO’s.

So this is my current problem. (There is no time limit on this problem. So i have no hurry with this.)

Did you understand what i mean / want ? :slight_smile:

But the current spec of the Analog and digital IO’s would realy interest me…

best regards,
Trider


#8

You can use the IO40 board to get all digital pins you need. For analog pins, you can connect any SPI, I2C or one wire ADC chip. Some of these chops are DIP so you can easily solder a board yourself. If you are not good with making boards, then you can easily connect any ready board that has one of the interfaces available on FEZ. This is an example but you have to make sure it will work http://mayhewlabs.com/arduino-mux-shield


#9

thx thats perfect…

Thats exactly what i was looking for. I will try out some sample programming for this “addon”.

Thank you very much.

best regars,
Trider


#10

What about chaining up a few IO40 boards and plugging i2c device into each of them? will it work?


#11

You can use an Analog Multiplexor to work with the Analog Inputs. These turn one Analog channel into 16:

Since there are 8 channels on board, theoretically this can be expanded to 128 Analog Inputs. The range would be the same 3.3V as the original pins, and you can use the same control lines for all the chips, you’ll just have to keep track of what you are looking at. You’ll also need to keep in mind the settling time on the AIN channel when switching the multiplexor chip (typically you wait a few uS then average 10 or more readings to get a value).

By the way, that same multiplexor chip can be used as a digital port expander.

If you are working with higher voltage analog sensors, you’ll need to divide the value down to 3.3V max, as applying more than 3.3V to the analog input pins can damage the MCU.


#12

IO40 board is a generic solution to give you control of many digital lines with a small number of uC lines consumed.

The way I2C is implemented on Fez it needs direct control of the i2c lines so a port extender solution won’t really work. you could try bit-banging the IO lines on the IO40 to emulate I2C but you won’t get the native I2C working thru a single IO extender let alone multiple.


#13

What exactly are you trying to accomplish? Maybe there is a better way we can show you.