How long can the Propeller stand 5v?
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My 3.3v regulator (LP2950-3.3) seems to be supplying 5.3v to the Vdd pins of the Propeller DIP chip.
I still don't know why.
When the Propeller chip is not connected, the Vdd pins measure 3.3v.
I removed the power about 20 seconds later when I realized this.
Do you think the Propeller is dead?
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I still don't know why.
When the Propeller chip is not connected, the Vdd pins measure 3.3v.
I removed the power about 20 seconds later when I realized this.
Do you think the Propeller is dead?
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
www.fd.com.my
www.mercedes.com.my
Comments
Do you have a bypass capacitor near the output of the regulator?
If not the regulator may oscillate under load and that is the voltage you are seeing.
Cheers Azlan.
One of the IO pins is getting 6v through a 3.9k resistor. Thanks.
I have now removed this resistor.
I wonder if it has killed the Propeller chip......
BTW,
I found that when the Prop Plug is plugged in to my board, it forces the Propeller chip's Vdd to rise up to about 4v.
The source of this high voltage seems to come from the TX and Res pins of the Prop Plug.
Is this normal?
I am still unable to program the Propeller chip, now I get the "No Propeller Chip found on any serial port" message,
even though both Prop Plug LEDs now blink when I try to "Identify Hardware".
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www.fd.com.my
www.mercedes.com.my
How many volts you got being output from the Prop Plug Tx and Res pins while plugged into a board?
I changed to a new propeller D40 chip, but still cannot program.
I double checked the Tx and Rx pins are not reversed.
This is the 1st time I use this board and this Prop plug.
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www.fd.com.my
www.mercedes.com.my
TX (Pin 40) 3.37 V
Do you get echo (in a terminal program) if you short TX and RX in the prop plug (unplugged from any board) ?
Do the regulator work ? (After getting 5V in its output)
The regulator seems to be robust.
I tried shorting Tx to Rx in the Prop plug as you suggested.
Only the blue LED blinks when I type something on the keyboard, using Parallax Serial Terminal program.
The Red Led does not blink. No echoing.
Looks like the Problem is with the Prop Plug.
Unfortunately I don't have a spare Prop Plug......
Looks like have to abandon my 1st real Propeller board project until I can get another Prop Plug, or should I put the Prop plug into a reflow oven?
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www.fd.com.my
www.mercedes.com.my
Post Edited (william chan) : 8/18/2008 12:07:47 PM GMT