RE: [ts-7000] Re: only DIO 1,3,5,7 works

[salva g <>]

...and could be pressed any switches i want at the same time? or only one?

---

To:
From:
Date: Tue, 29 Sep 2009 19:12:50 +0200
Subject: RE: [ts-7000] Re: only DIO 1,3,5,7 works

 

thanks this help very much.
then, i could have 16 I (not only 8) if i connect my switches like this?

http://www.8051projects.net/keypad-interfacing/keypad-schematic.gif

and, will i need some resistor when the low became high?

---

To: .com
From: com
Date: Tue, 29 Sep 2009 14:43:25 +0000
Subject: [ts-7000] Re: only DIO 1,3,5,7 works

 

--- In m("yahoogroups.com","ts-7000");">.com, salva g <salvagrana@...> wrote:
>
>
> Hi
> i am working with this code(button sample) but only responds with pins DIO nº1,3,5,7 when they are shorted to earth by pin DIO nº2. Why 9,11,13,15 does not work?
>

If you read the code, you will see that it sets the lower 4 pins to be inputs and the upper 4 to be outputs.

The keypad is a matrix of switches so you set one of the outputs high and see if any of the inputs becomes high. That's how you can connect 16 switches (4 x 4) on 8 (4+4) DIO pins.

>
> *PBDDR = 0xf0; //upper nibble output, lower nibble input
> *GPIOBDB = 0x01; //enable debounce on bit 0
> state = *PBDR; // read initial state
>

---

Charlas más divertidas con el nuevo Windows Live Messenger

---

Comparte tus fotos con tus amigos. Más fácil con Windows Live

__._,_.___

Your email settings: Individual Email|Traditional
Change settings via the Web (Yahoo! ID required)
Change settings via email: =Email Delivery: Digest | m("yahoogroups.com?subject","ts-7000-fullfeatured");=Change Delivery Format: Fully Featured">Switch to Fully Featured
Visit Your Group | Yahoo! Groups Terms of Use | =Unsubscribe

__,_._,___