Attiny25 RSTDISBL fuse programming how? ASM

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i am at the point of needing to program fuses in an attiny 8 soic. i have code that works (could be better, but this is the next step) and i need PB5, the RESET pin. i know that programming rstdisbl will prevent further programming via the SPI port. i just want to make sure how to do this corectly, as i only have 2 avrs, and can only spare one.

how do i programm RSTDISBL

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With your programmer and its programming software. Let us know what those are and we can help you better.

Regards,
Steve A.

The Board helps those that help themselves.

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Explain your i/o requirements. There are several tricks for 'sharing' pins.

The easy solution is to debug with a 'similar' Tiny with more pins.

I would avoid the RSTDISBL until you are finally debugged.

David.

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Quote:

I would avoid the RSTDISBL until you are finally debugged.

I concur--fussing with RSTDISBL on an apparent "first project" may be a recipe for disaster.

I suppose this is a case where HV programming might be helpful. It doesn't sound like OP has a Dragon or STK500 lying about.

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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well, its not a first project. i did manage to set the fuse. i wish i had a hv programmer...... just a USBASP.
thanks anyways,
nemo

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If a STK500 costs you $80 and a tiny25 costs you $1, it is cheaper to throw away 70 tiny25s.

You have chosen a small pincount Tiny. Just treat them as OTP.

If you are desperate to lose the /RESET pin, upload a bootloader into the chip. You will still need to comunicate with the bootloader via a pin.

danni has created bootloaders for anything. You will have to understand what you are doing.

David.

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I develop also with an ATtiny25 and all 6 IOs in use.
No problem, since I use a bootloader.

Peter

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david.prentice wrote:
If a STK500 costs you $80 and a tiny25 costs you $1, it is cheaper to throw away 70 tiny25s.
...but a net $10 for a STK500 after you've emptied your bin of OTP'ed Tinys is a good deal :)

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Look carefully at the posts that involve 'Tiny + RSTDISBL'.

Most of them come from hobbyists that possess one Tiny and a home-made ISP programmer.

They all want to do HV programming on the cheap.

In fact you can do the HVSP programming fairly simply. HVPP requires so many pins that it begins to get complicated. And of course with either HV option, a SMD device needs unsoldering from the pcb first.

Developing any AVR program on a similar but 'bigger' device is not only easier but cost-effective. e.g. developing on a $2 Tiny and recompiling for the target $1 Tiny.

The OP with 70 'dead' Tinys can ask a neighbouring Freak to restore them with a STK500 for $2 of postage. (and possibly beer or sandwiches)

David.