AVR-Chat

I've never attempted to use any of the AVR's with the store program
memory instruction...but I can't help but notice there's an interrupt
vector (and therefore a corresponding flag somewhere) called "SPM
READY" (Store Program Memory Ready).  Is your program using this
interrupt (or checking the flag manually) to make sure it's ready?



--- In AVR-Chat@yahoogroups.com, "Dave VanHorn" <microbrix@...> wrote:
>
> 
> Hmm.. Having much fun trying to implement this..
> 
> The basics of the Xmodem transfer protocol are working, and I get 128 
> byte packets from the host.
> 
> But putting them into program memory isn't working out right.
> 
> I have a register that counts packets from the host, of course it 
> rolls at 255, so I grab another register that counts rollovers.  1024 
> packets of 128 bytes fills a M128.  Here's how I translate the packet 
> count to the write address:
> 
> ;
> ;***********************************************************
> ;
> ; Create the page pointer in three DIFFERENT registers.
> ; from the Xmodem packet count, and ITEMP, which is used
> ; as the high byte, since we have no INTS at this point.
> ;
> Loader_MakePage:
> 	lds	TEMP,XmodemBlk		;
> 	call	Pong			;
> 
> 	clr	ZL			;
> 	out	RAMPZ,ZL		;
> 	;   RAMPZ       ZH       ZL
> 	;00000000 xxxxxxxx 00000000
> 
> 	lds	ZH,XmodemBlk		;The packet number
> 	;00000000 pppppppp 00000000
> 
> 	dec	ZH						;
> 	;packet 1 goes to block zero
> 	;00000000 bbbbbbbb 00000000
> 
> 	lsr	ZH					
> 	;shifts a 0 into MSB of ZH
> 	ror	ZL					
> 	;shifts carry into MSB of ZL
> 	;   RAMPZ       ZH       ZL
> 	;00000000 0bbbbbbb b0000000
> 	;       |          ||    ||
> 	;       |          ||    |\----- Which byte within word
> 	;       |          |\----\------ Words within page
> 	;	\----------\------------ Pages
> 
> 	mov	TEMP,ITEMP	;UGLY fix for how they bastardized the
> 	andi	TEMP,$03	;000000xx
> 	breq	MakePage_NOZ	;If neither bit is set, then done.
> 
> 	sbrc	TEMP,0		;If lsb is set, then set MSB of ZH
> 	ori	ZH,$80		;dosen't touch TEMP
> 	;00000000 Bbbbbbbb b000000
> 
> 	sbrs	TEMP,1		;if b1 is set, then set B0 of RAMPZ
> 	rjmp	MakePage_Noz	;
> 	ldi	TEMP,$01	;
> 	out	RAMPZ,TEMP	;
> 
> 	;00000001 Bbbbbbbb b0000000
> 	;       |          ||    ||
> 	;       |          ||    |\----- Which byte within word
> 	;       |          |\----\------ Words within page
> 	;       \----------\------------ Pages
> 
> MakePage_Noz:
> 	in	TEMP,RAMPZ	;So I can see the adrs on the LA
> 	call	PONG
> 	mov	TEMP,ZH
> 	call	Pong
> 	mov	TEMP,ZL
> 	call	Pong
> 	ret
> ;
> ;***********************************************************
> ;
> 
> What's happening, is that it seems to be erasing EVERY page, but 
> writing every OTHER page, although I can't tell if it's wrapping, or 
> exactly what is going on..  The "pong" statements are my byte in PWM 
> output on a single pin, and that shows me what I expect as the 
> packets come in.
>