Newbie

[cardkicker]

I want to program the AT90S2313 to blink a light just something to get me started, i have the 2313 pdf complete and i dont understand much of it also i have avr studio and i can see the ports such as DDRB, PortB and PinB butt i just aint getting the ideal of how this works. I can right code such as...
.include "2313def.inc"
rjmp main

main:
ldi r16 ;I no r16 is a registor butt what is it for?i dont
out Portb,r16 ;understand
Please help if can???

 

[checkmate]

Let me take a jab at it, although I don't know any avr and just read the 2313 datasheet for the very first time. I remember AVRs have many working registers as opposed to PICs which only have one, so I assume R16 is one of them.

Now, LDI is supposed to have 2 operands, Rd,K and Rd <- K.
So I guess it's putting constant K into Rd.
So are you missing an operand here?

Next, the OUT command only accepts a value from a register. You can't throw it a constant and expect it to automatically put the value in a register, and then execute the OUT command. That is why we need to pass it a value via r16. Is this where you are unsure of?

 

[RandomAccess]

Source Code

Hello

ldi (Load Imidiate) r16, 0b11111111 (or 0x1f[forhex])

That will load 8-bit into register 16. Notation of such commands is alway-> target, source

out PORTB, r16

Did you define DDRB fully as exit?

Do so in main:
ldi r16, 0b11111111
out DDRB, r16
for the counter
ldi r16, 0b00000000
ldi r17, 0b00000000
ldi r18, 0b00000001

But that wont get your LED blink'in. I suggest you wont even see it flash. The Micro will work with its Core speed. Estimated 10 or 24 Mhz

You will need to set a routine (a counter) and a bit rotation to see it blink.

mainloop:

wdr

echo:

inc r16
brne wait
inc r17
brne wait
rol r18
out PORTB, r18
wait:
rjmp mainloop