Trinket reset and disabling boot loader

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robert_david
 
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Trinket reset and disabling boot loader

Post by robert_david »

Two questions please (I'm just new to using Trinket & Trinket Pro, 5V versions));
Firstly the PDF "Introducing Trinket" mentions the Reset pin but does not specify the nature of the signal that must be applied to the pin to reset the device. Is it a positive 5V pulse if so of what duration?
Secondly for the project I have in mind I want the device to go straight to run the sketch/code and not spend 10 sec in bootloader mode; how can I achieve this?
I have searched the forum and if the answers to my questions are there I have not found them or failed to recogniose them as the answers because of a lack of knowledge (for example when I look at the pin-out for the Tiny chip I have no idea what some of the abtreviations INTO, PCINTS etc mean!)
Help would be much appreciated

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dastels
 
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Re: Trinket reset and disabling boot loader

Post by dastels »

Reset connects momentarily to ground (ie. logic low). The exact requirements depend on the processor. For the ATtiny85 the low pulse has to be at least 2.5 microseconds long.

To avoid the bootloader I suspect you'll need to work at a level below the USB bootloader (i.e. not have a bootloader), flashing your code directly into the chip using an embedded development tool (i.e. not Arduino)... possibly ATMEL Studio or IAR.

As for explanation of everything about the ATtiny85, see the datasheet: https://ww1.microchip.com/downloads/en/ ... asheet.pdf.

Finally, I advise you use something other than the Trinket. It's an old design and uses a software USB stack that doesn't work very well with modern computers/USB. See the warning on the product page:
Deprecation Warning: The Trinket bit-bang USB technique it uses doesn't work as well as it did in 2014, many modern computers won't work well. So while we still carry the Trinket so that people can maintain some older projects, we no longer recommend it. Please check out the Trinket M0. It has built-in USB, more capabilities, and is comparable in price!
Dave

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robert_david
 
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Re: Trinket reset and disabling boot loader

Post by robert_david »

Many thanks for a clear and qucik reply - it is much appreciated. With reference to your reply about not having the bootloader <I suspect you'll need to work at a level below the USB bootloader (i.e. not have a bootloader), flashing your code directly into the chip using an embedded development tool (i.e. not Arduino)... possibly ATMEL Studio or IAR.> I think I need far more information/guidance to be able to follow your advice - a clue as to where to look for such help would be appreciated.

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dastels
 
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Re: Trinket reset and disabling boot loader

Post by dastels »

Here's something that might help and still uses Arduino and an Arduino UNO. It seems like a reasonable approach.

https://circuitdigest.com/microcontroll ... ng-arduino

Dave

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robert_david
 
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Re: Trinket reset and disabling boot loader

Post by robert_david »

Again many thanks for your reply; I have had a VERY brief look at your recommendation and will study it more fully when I get a chance,

Apologies for the short delay in thanking you - too many family things to do!

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