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Vicne · 02-15-2006, 02:10 AM

Quote: Originally Posted by Ale

I think that if the spikes are so high they can pass the divider, the drop of 2,5V without the divider isn't enough.

So, if my understanding is correct, you think it's due to noise and not to a threshold problem, like I'm misusing the RS232 input by using it as an inverter, or the internal resistor is at the boundaries of the spec or something ?

Quote:

Or the spikes aren't so high but enter from the gnd pin of max232, if this is the case it is better to filter with the 10 uF capacitor near V+ and GND pins.

I'll put the 10 uF capacitor for sure, just have to find time to go to the nearest electronics shop - when it's open :-)

Quote:

Or try adding another 33K resistor connected between rx pin and V- of charge pump (-5V).

Wow, sorry to bother you again as you're helping me, but can you give a few words of explanation about the goal of this resistor ? Drag the voltage down further ?

Thanks for your unvaluable help.

02-15-2006, 02:10 AM	#89
Vicne Variable Bitrate Join Date: Apr 2005 Location: Belgium Posts: 325	Quote: Originally Posted by Ale I think that if the spikes are so high they can pass the divider, the drop of 2,5V without the divider isn't enough. So, if my understanding is correct, you think it's due to noise and not to a threshold problem, like I'm misusing the RS232 input by using it as an inverter, or the internal resistor is at the boundaries of the spec or something ? Quote: Or the spikes aren't so high but enter from the gnd pin of max232, if this is the case it is better to filter with the 10 uF capacitor near V+ and GND pins. I'll put the 10 uF capacitor for sure, just have to find time to go to the nearest electronics shop - when it's open :-) Quote: Or try adding another 33K resistor connected between rx pin and V- of charge pump (-5V). Wow, sorry to bother you again as you're helping me, but can you give a few words of explanation about the goal of this resistor ? Drag the voltage down further ? Thanks for your unvaluable help. __________________ Vicne SPDIF CarPC V2 - Tuner List CD Changer Emulator - Chris Conty Last edited by Vicne; 02-15-2006 at 04:48 AM.