You have to configure PORTA as fully digital, otherwise, when you do a bsf
PORTA,n the other pins get cleared for you.

writing b'00000110' to ADCON1 (0x9Fh) will do this.

The other option would be to have a shadow register for PORTA, and do the
bsf / bcf on this, then move the whole register to the port at once.

Hope this helps,

Regards, Kevin



----- Original Message -----
From: "Glenn Paul Vendiola" <gpvendiola@ONEBOX.COM>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Tuesday, May 22, 2001 6:10 AM
Subject: [PIC]: Device I/O 3rd part


> Hi, yup maybe it's better for me to discuss my application for a while
> so that somebody can help me.
>
> First, used PortA pins are all outputs and used PortB pins are all inputs.
>
>
> RB1, RB2, RB4, and RB5 receive the sensor inputs (high or low)which are
> latched by a D-flipflop.
>
> RA0, RA1, RA2, RA3 are used to clear the D-flipflop of each sensor
respectively.
>
> What the uController is doing is that it polls each sensor repeatedly
> and compares it to a certain value then responds accordingly.
>
> For example... If RB1 sees 100 "gray" (a mixture of high and lows) values
> without being reset, it will send a count signal. If RB1 sees 20
consecutive
> "Low" values, the counter will reset the incrementor.
>
> This approach works well with only one channel being used. But when I
> enable all 4 channels. I get something unexpected. It does not count
> and the d-flipflop is reseted rapidly.
>
> I placed a variable "watcher" that has a value of the frequency of sensor
> resets. I found that I needed to reset the sensor's d-flipflop every
> 3 mainloops to have it working the way I wanted it to. If I take that
> out, the D-flipflop will continue to be set even after the event of
blocking
> the light sensor is over.
>
> Please see the code that I've attached in my previous email.
>
> Thanks and hope this will do it.
>
> Glenn
>
> __________________________________________________
> FREE voicemail, email, and fax...all in one place.
> Sign Up Now! http://www.onebox.com
>
> --
> http://www.piclist.com hint: PICList Posts must start with ONE topic:
> [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads
>
>
>

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads