I've been toying around with attiny45 avr's, and am currently at a point where I need an extra i/o pin so I wad thinking about disabling the RESET pin.
From what i've read, the tl866 supports HVSP, so does this mean I can recover the RESET pin fuse with the tl866?
I don't see any any toggle switch in the software, so does the tl866 always use HVSP on these attiny's?
Anyone can actually confirm?
EDIT:
I just went ahead and took the risk of having a unsable tiny45, but I can confirm that the TL866 can indeed reset the fuses. I disabled the RESET pin (HFUSE 0x5F), and was able to read and rewrite the program & fuses without a problem.
i'll be quoting myself, but i'm confused.
Upon first programming my attiny45 with RESET disabled (E2 5F fuses), I am able to reprogram the fuses, and read & verify RESET is enabled again.
The tiny lets me erase, program, read... so I see no problem.
Now after building it into my project, I was not satisfied with the code, so I wanted to reprogram it (knowing it worked before). But now it's not longer working. I am not able to reset the fuses, and reprogram/erase/id the tiny..
first time i thought i had accidentely disabled spi also (so i guess i would need a HVPP), so second time i made sure the fuses were set correctly. but I'm up to 2 unusable mcu's now.
This really has me scratching my head right now...
The only explanation i can come up with, is that the fuses only come into effect, upon first powerup and running the code.
That would explain why i can enable/disable the fuses upon first programming/testing. but once it runs the code/powers on, the reset would effectively be disabled, and the tl866 is not really supporting HVSP.
EDIT:I'll be damned.... apparently it works fine in the soic ziff socket...
So, here's the story. I program the soic8 ATtiny45 in a ziff socket. Then I solder it to a dip8 breakoutboard, so i can wire it up in my project.
Now when I wanted to reprogam it, i dosldered it from the project, wired it to a 8pin ribon cable, that goes to a pinheader, into the TL866 Socket.
Apparently this was causing my headache. As a desperate measure, i put the heatgun to it, desolderen the ATtiny from the breakout, it it worked just find in the soic8 ziff socket
Still have no clue as to what the problem is. tried 2 different ATtinys on 2 different breakoutboards, both the same problem, breakoutboards checks out fine, the ribbon cable measured fine pin-for-pin, the pinheader checks-out fine... i'm clueless. but atleast I can use my ATTinys again.