On Sun, Jul 27, 2014 at 1:04 PM, Miguel Garcia gacuest@gmail.com wrote:
We are designing a handheld-game console (based on EOMA-68).
great!
The problem is that EOMA-68 has very few GPIO.
ah - it now has quite a few: 17 at the last count, however yes they are all multiplexed.
We have 17 digital buttons, 2 analog joystick ( http://www.digikey.com/product-detail/en/254TA103B50B/254TA103B50B-ND/175591... ) and 2 analog triggers ( http://www.digikey.com/product-detail/en/EVA-W7NR04B34/P13569-ND/1135944 ).
Luke will use on the tablet the next IC: PCA9536.
yep. it is a low-cost I2C 8-bit GPIO
However, this component does not meet our requirements.
no ADC...
Does anyone know a IC that meets these requirements (at least 17 digital buttons and at least 4 ADCs)?
that's quite a lot!
but you should be able to do keyboard matrix scanning to cover 16 buttons, 4 input 4 output... unless you really really want all possible button combinations, hmmm...
are there any keys which may not be pressed together, so you can do matrix-scanning on those, at least?
i will see if there is an I2C ADC/GPIO IC around... also now SPI is available so you could use that.
l.