Attiny461

[IDK]

AVR-USB seems to be the best thing ever, if I only could get it to work....

I'm using an attiny461V with the following setup:
D+ connected to PB6 (which is INT0) over 68 Ohm.
D- connected to PB5 over 68 Ohm and a 1.5 kOhm resistor connected to Vcc.
Should I connect them in any other way?
Should I order some 3V6 zenerdiodes?

Further I'm using two 1N4148 diodes to lower the input voltage to 3.52 V.

I'm trying to make the newest version of Easylogger run on it.
I changed some registers to match the pin layout of the 461 and the program runs fine on it, but when I connect to my windows machine, it says that it has found an unrecognizable device. Does this mean that the code doesn't work, or that the circuitry is wrong, or that it maybe could be either of them?

And does the internal PPL oscillator of the 461 work with easylogger?

Thanks in advance for any help.

[Grendel]

And does the internal PPL oscillator of the 461 work with easylogger?

You could try to configure the 461 using the PLL clock in high speed mode (16MHz CPU clock). Since the PLL is locked into the 8MHz RC oscillator it can by calibrated via OSCCAL. You will have to run the CPU at 5V for this tho, so you will need the 3V6 Z-diodes.

[giseburt]

I'm using an attiny461V with...
And does the internal PPL oscillator of the 461 work with easylogger?

Now, someone please correct me if I'm wrong (because I'd like this to work), but I think the PLL is not available in the V versions of the ATTiny{2,4,8}61 chips. (I'm not sure if you're using the V version or not...)

To quote Page 25 of the Datasheet:

The internal PLL in ATtiny261/461/861 generates a clock frequency that is 8x or 4x multiplied from a source input depending on the Low Speed Mode (LSM) bit.

And on page 1 it says:

–ATtiny261V/461V/861V: 0 - 4 MHz @ 1.8 - 5.5V, 0 - 10 MHz @ 2.7 - 5.5V
–ATtiny261/461/861: 0 - 10 MHz @ 2.7 - 5.5V, 0 - 20 MHz @ 4.5 - 5.5V

Unless I'm wrong (and I'd love to be) that means the V versions can't go over 10MHz, and don't have a PLL.

-Rob

[Grendel]

Good catch, I did not pay attention to the "V". Not sure the PLL is absent in the V version but the 10MHz speed grading alone makes this idea useless

[christian]

You can still try to get it running with the 12.8 MHz module. This should work on devices rated at 10 MHz.

[Grendel]

Oh, true. It does go up to 14MHz (somehow I thought it's only +/- 1MHz or so). Edit: ah, table 7-6 says 7.3-8.1MHz. Clashes w/ figure 24-35.

Quick question for Christian -- why 12.8MHz ? According to the 461 data sheet the oscillator could be calibrated to 12MHz as well.

[christian]

The 12 MHz module needs the precision of a crystal, the 12.8 MHz module does not. The additional 0.8 MHz are spent for a software PLL.

Regarding the conflict between table 7-6 and figure 24-35: The table documents guaranteed values, the diagram real, measured values. The diagram reflects reality very closely.

[IDK]

I didn't get it to work with the zenerdiodes, and I do got the V version... (the one's I bought it from didn't list it as a V version... hmm)

I bought a 16 MHz oscillator and I'm going to try to get that one to work.

[Grendel]

Thanks for the clarification.

16MHz may be too much of an overclock for the V version. I know of one user who sucessfully used a 12MHz crystal w/ the 461V tho.

[Guest]

"V" Devices use the same silicon as the non "V" versions.

With higher supply they behave linke the non V's.

Regards,

D.

[christian]

I was under the same impression (that the V types use the same silicon but are selected by parameters), but users reported that the same circuit works with a non-V type while it fails with a V type. This was at 16 MHz, as far as I remember.

[IDK]

First I tried the 12.8MHz mode.
It didn't work .

I finally got my 12MHz crystal and tried it.
It didn't work .

Then I noticed that the resistor for D- was on D+.
Fixed it and It works .

Thanks for the help!