More buttons and LED's

K. Reichman

Hi,
Please help me. I must have seven buttons on BS2. When I touch one button, BS2 must sent on serial character "1", and so on until character "7". There is 2 problems: 1. When I release one button, I want BS2 to continue to send the character, until I press the other button, .... 2. On each buttons is atached one LED. I want LED remain on after button is released.

PLEASE HELP ME !!!


Thanks


Valentin

Jon Williams

Here's·how I would do it:

Main:
· select =·NCD (INL & %01111111)
· IF·select = 0 THEN Main············ ' try again if none pressed

· OUTH = %00000000··················· ' clear old LED
· select = select - 1················ ' z-align
· HIGH select + 8···················· ' light new LED
· SEROUT Sio, Baud, [noparse][[/noparse]"0" + select]··· ' transmit character
· GOTO Main

P0 - P7 are the button inputs (active high), P8 - P14 are the LED outputs

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Jon Williams
Applications Engineer, Parallax

Post Edited (Jon Williams (Parallax)) : 11/15/2005 1:15:26 PM GMT

metron9

Not sure how that works,

I read DCD sets a bit of a Word using a 4 bit value, that is it sets any bit 0 through 15 for the integer value 0 through 15 given as its input.

INL is an 8 bit value so bits 4 thru 7 are not looked at by the command.

results would be 2,4 16 and 256 for bit 0,1,2,3

Select is also a keyword so you cant use it as a variable

Could you just use

main:
ledvar=INL & %01111111 'Get the input bit that is set mask to 7 switches
outH=ledvar 'Set the bit to light the led (shift to position first depending on pins used)
output serial character
probbly pause for some delay
goto main


If that's wrong I must be in need of a vacation cause I just cant see how it works.

K. Reichman

Thanks for your answer...

For the moment, didn't work. Can you send me please a diagram with connection of one button and one LED please?

Jon Williams

Whoops, sorry, I should have used NCD instead of DCD -- that was written off the top of my head as an idea to give you guidance, and not intended to be a full working program.

NCD will return the input that is pressed (+1) -- that way you get one value, even if you accidentally press two buttons.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Jon Williams
Applications Engineer, Parallax

metron9

There are so many things i don't know about Pbasic. I knew I could learn something new again, thank's for clearing that up Jon.

K. Reichman

On Parallax experiment #15 "Deboucing Multiple Inputs" it's an example about four inputs. How can extend for eight inputs?

Tx

Jon Williams

It's easy: use a byte variable instead of a nibble, and read a byte-wide port (i.e., INL or INH) instead of a nibble-wide port.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Jon Williams
Applications Engineer, Parallax