Hi there,
I am using DT's MIBAM routine with 20 port/LEDs.
With 18F452, set to 4x10Mhz PLL clock, chip does not work.
It works with 20Mhz HSOSC with no problem.
Any ideas why it does not work with 40MHz?
I will use 24 ports with 40MHz.
Thank you.
MIBAM and 40Mhz (10Mhz x 4 PLL) 18F452 - Chip does not work
Hi there,
I am using DT's MIBAM routine with 20 port/LEDs.
With 18F452, set to 4x10Mhz PLL clock, chip does not work.
It works with 20Mhz HSOSC with no problem.
Any ideas why it does not work with 40MHz?
I will use 24 ports with 40MHz.
Thank you.
"If the Earth were a single state, Istanbul would be its capital." Napoleon Bonaparte
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Re: MIBAM and 40Mhz (10Mhz x 4 PLL) 18F452 - Chip does not work
Hi Sayzer,
Does it do anything at all? Or is it just dead at that point?
DT
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Re: MIBAM and 40Mhz (10Mhz x 4 PLL) 18F452 - Chip does not work
The circuit has a digit to show the animation mode number. At 40MHz, sometimes( ! ) the digit comes and goes. But port pins used for MIBAM never works.
Thank you Darrel.
"If the Earth were a single state, Istanbul would be its capital." Napoleon Bonaparte
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Re: MIBAM and 40Mhz (10Mhz x 4 PLL) 18F452 - Chip does not work
Can you confirm that the PIC does indeed work at 40MHz? Maybe you are having a hardware problem with the oscillator (I had something similar once using a breadboard).
Can you add a simple test, maybe blink an LED at a fixed interval?
My Creality Ender 3 S1 Plus is a giant paperweight that can't even be used as a boat anchor, cause I'd be fined for polluting our waterways with electronic devices.
Not as dumb as yesterday, but stupider than tomorrow!
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Re: MIBAM and 40Mhz (10Mhz x 4 PLL) 18F452 - Chip does not work
Sayzer,
After checking the program, going through the math, compiling for an 18F @ 40mhz and not finding anything wrong ... I put together a breadboard with an 18F4620 running at 40Mhz with a 10Mhz crystal and 24 LED's.
It works fine.
BAM_INFO says ...
Message[301]: MESSAGE: ('BAM_INFO' - MinPeriod= 173 inst, Cycle= 22774 inst, Pins= 24, FREQ= 219 Hz)
DT
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Re: MIBAM and 40Mhz (10Mhz x 4 PLL) 18F452 - Chip does not work
Thank you very much Darrel.
I also went through the hardware, and found nothing wrong.
10Mhz xtall, 15pf caps, HSPLL (DEF. OSC 40) does not work.
20Mhz xtall, 15pf caps, HS_OSC (DEF. OSC 20) works.
Testing it with 40Mhz using a test code (without MIBAM) is ok.
"If the Earth were a single state, Istanbul would be its capital." Napoleon Bonaparte
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Re: MIBAM and 40Mhz (10Mhz x 4 PLL) 18F452 - Chip does not work
Sayzer was using an 18F452, not an 18F4620, maybe it's a problem with a particular chipset and not the 18F family?Originally Posted by Darrel Taylor
One thought, Sayzer, did you try with another 18F452? That would rule out a defective unit.
And if you want to rule out the breadboard, try it on another one. I've had only one breadboard so far with a defective track in it.
And a really dumb question, did you confirm that power to the circuit was good? Forgetting to readjust the voltage or current on a variable power supply like the one I use could make for freaky results; not saying that I ever did that noob mistake.
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