Probably a dumb question....

USB AVR Programmer and SPI interface. Adafruit's USBtinyISP.

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magician13134
 
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Probably a dumb question....

Post by magician13134 »

Can this program PICs? I don't think it can, but I don't know ANYTHING about them....

adafruit
 
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Post by adafruit »

nope. avrdude can only program avrs

vibrion
 
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another dumb one

Post by vibrion »

One thing I cannot understand is if in ISP programming the circuit needs an external clock or could be programmed with internal one. In some atmel documention, I've read about not to connect circuit power supply at programming time. Programmer is suppoused to supply the power or it depends on programmer type?. Thanks in advance i'm just starting with avrs (i came from PICs and 8051 world).
PS: to make it more complex: Im an LINUX user only ! :lol:

adafruit
 
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Post by adafruit »

are you asking about clocking or power? and is this in specific about usbtinyisp programmers or 'in general'?

Entropy
 
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Re: another dumb one

Post by Entropy »

vibrion wrote:One thing I cannot understand is if in ISP programming the circuit needs an external clock or could be programmed with internal one. In some atmel documention, I've read about not to connect circuit power supply at programming time. Programmer is suppoused to supply the power or it depends on programmer type?. Thanks in advance i'm just starting with avrs (i came from PICs and 8051 world).
PS: to make it more complex: Im an LINUX user only ! :lol:
Well, your question is somewhat hard to understand, but:

1) If the AVR is fused to use the internal RC oscillator, I believe you can program it without an external clock. I don't know what happens if it's fused to use an external clock source and you try to ICSP it. The ICSP does (to my knowledge) have its own serial clock, but all documentation I've seen implies that the CPU's own clock (and clock rate) is involved in ICSP.

2) I'm not sure if it is required to remove external power for programming, it could depend on the programmer being used. The USBTinyISP has the ability to supply power to a circuit, but this can be disabled by removing a jumper. Using the "programmer power supply" when the circuit is externally powered would probably be bad.

vibrion
 
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Joined: Tue Jan 15, 2008 5:28 pm

Power and clock

Post by vibrion »

Thanks for the responses. Im talking in general. As I read in posts it seems that external clock is needed at programming moment.
And yes these are two different questions , power to the microcontroller depends on programmer: some provide it, other not.

adafruit
 
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Post by adafruit »

hi please don't hijack this post...make a new post with your questoin in the brand new "Microcontrollers" forum (scroll down, its at the bottom) :)

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