Objective Development Forums

Mega324P and AVR-USB

2007-09-27T11:02:37+02:00

Hi! Is you MCU running at 5V or 3.3V? If 5V are you using proper zener diodes? Did you try with another computer?

Statistics: Posted by butrus.butrus — Thu Sep 27, 2007 11:02 am

USB on ATmega324P

2007-09-22T22:25:52+02:00

I just got AVR-USB working fine on my ATmega324P.

I am using PORTD, PD2(INT0) for DATA+ and PD3 for DATA-.
- no problems.

Just be careful with your usbconfig.h settings.

Statistics: Posted by Guest — Sat Sep 22, 2007 10:25 pm

Mega324P and AVR-USB

2007-08-02T14:23:37+02:00

If you started with HIDKeys, you probably get the log from

Code:

int   main(void)
{
uchar   key, lastKey = 0, keyDidChange = 0;
uchar   idleCounter = 0;

    wdt_enable(WDTO_2S);
    hardwareInit();
    odDebugInit();
    usbInit();
    sei();
    DBG1(0x00, 0, 0);

This would indicate that you get a controller reset.

Statistics: Posted by christian — Thu Aug 02, 2007 2:23 pm

Mega324P and AVR-USB

2007-08-02T08:18:40+02:00

Ok, I managed to hookup USART, and when I plug in a USB cable, I get 00: 00 (debug set to 2)

Joe

Statistics: Posted by Guest — Thu Aug 02, 2007 8:18 am

Mega324P and AVR-USB

2007-08-01T16:36:59+02:00

The debug log

ff:
ff:
ff:
...

is printed while the USB is in RESET state. This means that the driver reads both, D+ and D- as zero. See usbdrv.c and search for DBG1(0xff, 0, 0); to see how reset is detected.

Statistics: Posted by christian — Wed Aug 01, 2007 4:36 pm

Mega324P and AVR-USB

2007-08-01T16:22:36+02:00

Hi,

i have the same problem. Also when i enable the debug interface by DEBUG_LEVEL=2, all i get is FF: FF FF FF FF FF ... and so on. Whats wrong there? ... all i changed from original powerswitch SW is:
- PortD instead of PortB
- PinD.3 instead of B.0 for D-
- PinD.2 instead of B.1 for D+ (INT0)
- use ATMega168-20 instead of ATMega8-16 (had to change register names for ee-write/read functions)

thanks in advance,

Robert.

Statistics: Posted by Guest — Wed Aug 01, 2007 4:22 pm

Mega324P and AVR-USB

2007-07-30T16:22:39+02:00

And you are sure you compile for 12 MHz and not with an assembler module for another frequency. In this case you should really try to get a debug output with -DDEBUG_LEVEL=2...

Statistics: Posted by christian — Mon Jul 30, 2007 4:22 pm

Mega324P and AVR-USB

2007-07-27T05:55:44+02:00

Hi Christian,

Ok, I've double verified the clock frequency with the _delay_ms() function - it is 12Mhz, and generates perfect timing. I "think" the values for the fuses are what they should be - I'm using AVRStudio, and picking what looks to be the equivalent setting on the Mega324p (no division of clock frequency, etc). I've also placed a few LED toggles at key points in the usbdrv.c file as a debug check (waiting for some parts in order to use USART) - they do change upon USB cable insertion, so it appears everything is working well in the sense of interrupts. Should hopefully have parts tomorrow, and can get more in depth look at what's happening.

Joe

Statistics: Posted by Guest — Fri Jul 27, 2007 5:55 am

Mega324P and AVR-USB

2007-07-23T13:44:13+02:00

You can safely use bits D0 and D2, I do this in all my projects.

Please verify your basic configuration:

Clock frequency. Write a simple test program which uses _delay_ms() from util/delay.h to generate a known frequency and check whether it's correct. The processor has a clock prescaler which might be active.
Fuse values: Did you use the same hexadecimal fuse values as for the Mega8, or did you use the same options? Bit locations are often not consistent between AVR versions.
Please check your I/O initialization. Instead of starting the driver, check that both USB lines are inputs and that D+ triggers an interrupt.

Statistics: Posted by christian — Mon Jul 23, 2007 1:44 pm

Mega324P and AVR-USB

2007-07-21T19:07:29+02:00

iphi wrote: D0=> D-, D1=>D+ and D2=INT0=>D+

You might want to try this.

Ok, gave that a try, and still no go - thanks though!

Joe

Statistics: Posted by Guest — Sat Jul 21, 2007 7:07 pm