Re: [Amforth-devel] Question on Baud rates

[Dennis C. <den...@gm...>]

On Sun, Jan 30, 2011 at 5:24 PM, pito <pi...@vo...> wrote:

> Dennis,
> this works for me (from template.asm):
> ........
> .include "devices/atmega1284p/device.asm"
> ; amforth needs two essential parameters
> ; cpu clock in hertz, 1MHz is factory default
> .equ F_CPU = 22000000
> ; initial baud rate of terminal
> .equ BAUD = 115200
> .set USART_B_VALUE = (1<<TXEN0) | (1<<RXEN0)
> .equ WANT_ISR_RX =1;
> .if WANT_ISR_RX == 1
> .set USART_B_VALUE = (1<<TXEN0) | (1<<RXEN0)| (1<<RXCIE0)
> .else
> .set USART_B_VALUE = (1<<TXEN0) | (1<<RXEN0)
> .endif
> ; 8N1 is commonly used
> .equ USART_C_VALUE = (3<<UCSZ00)
> .include "drivers/usart_0.asm"
> .......
> P.
>
>
Pito, I have pretty much the same thing (except for freq, and baud). I
noticed that you hard coded the device.asm where as mine did not have a
path. It did not seem to make a difference when I tried hard coding it
though.

One thing that did jump out at me, you have a 22Mhz clock on your
atmega1284p?

I moved my baud in the template.asm back up to 9600 and now I get 1200 baud.
It always seems to 1/4 of the requested baud.

Dennis

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