Do without AVR bootloader

Discussions related to MegaDrum Hardware

Do without AVR bootloader

Postby Ken Forgettable » Fri Apr 24, 2009 2:33 pm

With the addition of a single resistor and a short header cable I think it should be possible to ICSP the AVR using USB.
Ken Forgettable
 
Posts: 402
Joined: Tue Jan 06, 2009 5:04 pm

Re: Do without AVR bootloader

Postby dmitri » Fri Apr 24, 2009 2:52 pm

It should.
dmitri
Site Admin
 
Posts: 8709
Joined: Fri Aug 03, 2007 8:05 pm

Re: Do without AVR bootloader

Postby Ken Forgettable » Fri Apr 24, 2009 4:58 pm

Well what about one less resistor?
Using Synthex v2 schematic where P - ICSP_18F2550 and A - ICSP_Atmega
+ Cut out R8.

P.1 to A.4
P.4 to A.1
P.5 to A.2
P.6 to A.3

I asked the bus driver - he said it would work :lol:
Ken Forgettable
 
Posts: 402
Joined: Tue Jan 06, 2009 5:04 pm

Re: Do without AVR bootloader

Postby dmitri » Fri Apr 24, 2009 5:25 pm

Ken Forgettable wrote:I asked the bus driver - he said it would work :lol:

And I agree with him.
dmitri
Site Admin
 
Posts: 8709
Joined: Fri Aug 03, 2007 8:05 pm

Re: Do without AVR bootloader

Postby Ken Forgettable » Fri Apr 24, 2009 6:03 pm

dmitri wrote:And I agree with him.

You speak Polish?

And while we're at it, what about moving LED contol to the PIC :geek:
Ken Forgettable
 
Posts: 402
Joined: Tue Jan 06, 2009 5:04 pm

Re: Do without AVR bootloader

Postby dmitri » Fri Apr 24, 2009 6:17 pm

Ken Forgettable wrote:
dmitri wrote:And I agree with him.

You speak Polish?

Very little.

And while we're at it, what about moving LED contol to the PIC :geek:

If there is a reason for this explained in simplified English.
dmitri
Site Admin
 
Posts: 8709
Joined: Fri Aug 03, 2007 8:05 pm

Re: Do without AVR bootloader

Postby Ken Forgettable » Fri Apr 24, 2009 6:25 pm

dmitri wrote:If there is a reason for this explained in simplified English.


The PIC does the MIDI and the LED is a MIDI indicator!

But what I'd really like is to get access to is TOSC1 - maybe dump the XTAL parts too?

Sleep on it eh?

[EDITED]
TOSC1 - er, XTAL parts! wrong thread I became deranged!
Last edited by Ken Forgettable on Mon Apr 27, 2009 8:48 am, edited 2 times in total.
Ken Forgettable
 
Posts: 402
Joined: Tue Jan 06, 2009 5:04 pm

Re: Do without AVR bootloader

Postby dmitri » Fri Apr 24, 2009 6:45 pm

Until somebody implements "bit banging" or Atmega SPI protocol in PIC18F2550 firmware, the bootloader stays put and the MIDI LED along with it.
dmitri
Site Admin
 
Posts: 8709
Joined: Fri Aug 03, 2007 8:05 pm

Re: Do without AVR bootloader

Postby Ken Forgettable » Sat Apr 25, 2009 12:45 am

[EDITED]
dmitri wrote:Until somebody implements "bit banging" or Atmega SPI protocol in PIC18F2550 firmware...

Code: Select all
if (msgparsestate==MSG_IDLE){
        ch=uart_getchar(1);
}else{
        ch=uart_getchar(0);
}
// parse message according to appl. note AVR068 table 3-1:
if (msgparsestate==MSG_IDLE && ch == MESSAGE_START){
        msgparsestate=MSG_WAIT_SEQNUM;
        cksum = ch^0;
        continue;
}


More of this clean looking code at http://www.tuxgraphics.org/common/src2/article05101/
Ken Forgettable
 
Posts: 402
Joined: Tue Jan 06, 2009 5:04 pm

Re: Do without AVR bootloader

Postby Ken Forgettable » Wed Apr 29, 2009 5:59 pm

I wonder what Atmel are up to?

Anyway, I think somebody could implement PS2 'intellimouse' input on the PIC too :?

Just two buttons and the scroll wheel would be needed from code like http://instruct1.cit.cornell.edu/courses/ee476/FinalProjects/s2004/jcc72/code.html
Ken Forgettable
 
Posts: 402
Joined: Tue Jan 06, 2009 5:04 pm


Return to MegaDrum Hardware

Who is online

Users browsing this forum: Google [Bot] and 91 guests