It's possibly a bad chip. Does only one Mega88 have this problem? Have you tried substituting another? Bad Chips DO get sold once in a while. Zack On Thu, Mar 8, 2012 at 10:42 AM, Dave <microbrix@gmail.com> wrote: > ** > > > Is this by chance in the debugger or jtag ice? > > > Tim Mitchell <tim@sabretechnology.co.uk> wrote: > > >OK so I've got this mega88 where some bits in registers R0-R15 appear to > be permanently set... > > > >if I do > > > >ldi R16,0 > >mov R1,R16 > > > >R1 has 1 in it!! > > > >Same code on a different mega - everything is OK. Avoid using R1 - > everything is OK. Has anyone ever seen anything like that? > > > > > >Then I have another mega88 on a different project. C software this time > (GCC) > > > >(Interrupts are not enabled) > >I am doing > >if (Value==0) EepromWrite(0x20,Value); > > > >which it's compiling as > >lds r24,0x0115 > >and r24,r24 > >breq +2 > >rjmp +362 > > > >However the EepromWrite is happening even when Value is zero, but when I > read back the eeprom values, it has stored 0x01. So it seems like the SREG > is corrupted somehow, ie the zero flag set when it shouldn't be. > > > >Help! am I going mad? > > > > > >-- > >Tim Mitchell > > > > > > > >------------------------------------ > > > >Yahoo! Groups Links > > > > > > > > > [Non-text portions of this message have been removed]
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Re: [AVR-Chat] weird mega88 problem
2012-03-08 by Zack Widup
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