Objective Development Forums

About RC12.8MHz.

2008-11-16T22:55:06+02:00

You can't use osccal.c anyway, because to code is too big for the ATTiny2313. The 12.8 MHz module is not suitable for the ATTiny2313.

Statistics: Posted by christian — Sun Nov 16, 2008 10:55 pm

7bit OSCCAL products

2008-11-15T05:59:11+02:00

ATTINY2313 OSCCAL length is 7bit.
The initial OSCCAL value is 128 in oeccal.c so ATTINY2313 starts OSCCAL=0 as slow 3.5MHz CPU clock.

Is step=64 in osccal.c better for 7bit OSCCAL products ?

Statistics: Posted by Guest — Sat Nov 15, 2008 5:59 am

About RC12.8MHz.

2008-11-05T13:13:09+02:00

Seems to be true: the Tiny2313 may not be able to reach 12.8 MHz...

This is not so much of an issue because it's hard to implement something useful in only ~ 300 bytes of code. The 12.8 MHz driver is much bigger than the other modules.

Statistics: Posted by christian — Wed Nov 05, 2008 1:13 pm

About USB2LPT6.

2008-11-05T04:23:50+02:00

I read it well, but did not come to understand a start.

I made a mistake in choice of fuse.
I am ATmega168: SUT[1:0 -10] You should have chosen CKSEL[3:0-0010].
When I use RC of tn2313 in your sentence and can proofread AVU-USB-HID, I can read, but is the interpretation wrong?
Can you let "16.5MHz" or "12.8MHz" act in tn2313-RC when they are possible?
I can find it in manual of tn2313, Figure 132 "only to 12MHZ".

I can add one pin, a port of 3pin in total by using inside RC oscillator by assigning reset to Port more.
Or I do it whether I connect 16MHz to xtal1 with an outside oscillator and get 2pin.

Statistics: Posted by apollononnno — Wed Nov 05, 2008 4:23 am

Re: To use RC12.8MHz in mega168?

2008-11-04T14:07:32+02:00

apollononnno wrote:ATtiny2313: SUT[1:0-10] CKSEL[3:0-0100].
ATmega168: SUT[1:0-10] CKSEL[3:0-1100].
Calibration Byte = 240 → f = 12.8MHz.
How should I use "libs-device" and "usbdrv?"

ATtiny2313: Selects internal 8 MHz RC oscillator with 65 ms start-up time
ATmega168: Selects low-power crystal oscillator with 1K clock cycles start-up time
That is wrong! For proper 16.8 MHz AVRUSB module, you don't need to change fuse settings, let CKSEL[3:0]=0010 and SUT[1:0]=10.
The calibration byte should be tuned by firmware, either after USB RESET (D- not required to route to an INT pin), or permanently (D- required to be routed to an INT pin, less code size). On ATmega168, every pin is interrupt capable, so, if you decide to use the latter version, no change in hardware is necessary.
You should use “osccal.h”+“osccal.c” to tune calibration byte after USB RESET, or “osctune.h” to tune permanently.
For a working example on ATmega8, see http://www.tu-chemnitz.de/~heha/bastele ... sb2lpt.zip and the directory src/firmware/USB2LPT6 inside.

Note that the 16.8 MHz module does fit into 2 KB program space of ATtiny2313 if you have good knowledge how to do. See same example for a working HID bootloader.

Statistics: Posted by henni — Tue Nov 04, 2008 2:07 pm

To use RC12.8MHz in mega168?

2008-11-04T13:27:07+02:00

The setting of ATtiny2313 is next.
SUT[1:0-10] CKSEL[3:0-0100].
The setting of ATmega168 is next.
SUT[1:0-10] CKSEL[3:0-1100].
Calibration Byte will become 12.8MHz with a value of the neighborhood of 240(F0).
How should I use "libs-device" and "usbdrv?"

Statistics: Posted by apollononnno — Tue Nov 04, 2008 1:27 pm

About RC12.8MHz.

2008-11-04T06:26:49+02:00

For fuse setting - look in the datasheet for the ATtiny2313. CKSEL[3:0] have to be changed as well as SUT[1:0].

Statistics: Posted by bearing — Tue Nov 04, 2008 6:26 am

There is a device of HID of tn2313.

2008-11-06T12:14:25+02:00

By the demand of the producer, I deleted URL.
The necessary person please search [hidspx].

Because this device is tn2313, it is lack in "RC12.8MHZ" and memory of "2 kbytes".
Can you change this in mega48,88,168?
What kind of operation is necessary for fuse, proguram to operate this in "RC12.8MHZ?"

Statistics: Posted by apollononnno — Mon Nov 03, 2008 5:05 am

About RC12.8MHz.

2008-10-31T05:38:26+02:00

I actually tried to see what happened in different temperatures. The code calibrates the frequency by measuring the intervals between marker pulses. When putting a bag of ice on the IC OSCCAL moved from 249 to 250. When putting the IC under a lamp OSCCAL went down to 248.

Those were not huge differences. 12.8 MHz will probably work in all temperatures humans tolerate (on 3.3 volts).

Statistics: Posted by bearing — Fri Oct 31, 2008 5:38 am

I thank for a very significant commentary.

2008-10-31T05:03:10+02:00

I take time and try inspection of the movement.

Statistics: Posted by apollononnno — Fri Oct 31, 2008 5:03 am