My LCD is high.
I have a little app that prints a string out to a SEETRON 216 LCD. When I end the program I get very odd looking charactors that very slowly fill the screen. But, when I send the pin HIGH when the program ends it's okay.
I thought I read some place that you generally don't want to leave pins high if you don't have too.
Comments?
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My project, the ElectricMotorcycle Dashboard: Em Dash
Post Edited (mreish) : 5/7/2006 8:42:52 PM GMT
I thought I read some place that you generally don't want to leave pins high if you don't have too.
Comments?
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
My project, the ElectricMotorcycle Dashboard: Em Dash
Post Edited (mreish) : 5/7/2006 8:42:52 PM GMT
Comments
If your application is driving loads (sourcing or sinking current through output-high or output-low pins) during SLEEP, current will be interrupted for about 18 ms when the BASIC Stamp wakes up every 2.3 seconds. The reason is that the watchdog-timer reset that awakens the BASIC Stamp also causes all of the pins to switch to input mode for approximately 18 ms. When the interpreter firmware regains control of the processor, it restores the I/O directions dictated by your program.
In your case your LCD is perceiving that as some character being sent...
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Chris Savage
Parallax Tech Support
csavage@parallax.com
So, in this situation, leaving the pin output high is not a problem.
The real problem is when you tie two outputs together, then try to make one output high, while the other outputs low. If you don't have a 220 ohm resistor between the two, the resulting wrestling match will burn out one or both of the pins.
Well, thanks for both replies. Problem solved!
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My project, the ElectricMotorcycle Dashboard: Em Dash