AVR-Chat

From page 7 of the data sheet:
"PEN is a programming enable pin for the SPI Serial Programming mode. 
By holding this pin low during a Power-on Reset, the device will 
enter the SPI Serial Programming mode. PEN has no function during 
normal operation." Note that it is only sensed during Power-on Reset. 
For normal SPI programming, PEN is not used. Tie it directly to Vcc.

Also, look at the Reset Logic diagram on page 48. This suggests that 
the CPU will be permanently reset if you tie PEN low.

Regards,
Les Grant.


On 12 Dec 2004 at 2:56, Ridho Alpha wrote:

> 
> hello...
> 
> i am starting to use ATMEGA128 right now..but i am a bit confused what /PEN pin is for??? how do use it???
> 
> do i just connect /PEN pin to 4K7 resistor and VCC???
> 
> please give same clues...
> 
> thank you
> 
> 
> ---------------------------------
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Les Grant. VK2KYJ.      Phone: 02 9896 7150 Fax: 02 9896 7153
Grantronics Pty Ltd     Int'l: +612 9896 7150, +612 9896 7153
ABN 46 070 123 643
PO Box 275, Wentworthville. NSW. 2145. Australia.            
http://www.grantronics.com.au  mailto:info@grantronics.com.au
Microcontroller Hardware and Software development:  Atmel AVR
8051 derivatives, 80C196 family, C, ASM, Digital and analogue 
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