Page 1 of 1
disable the UART transmitter on the 88
Posted: Tue Apr 07, 2009 1:42 am
by ulao
I'm having a very difficult time assessing the UART transmitter functionality. It would stand to reason that using the atmega88 style chip could compromise pins pd0 and pd1. My project is sort of stuck using the pins for my usb communication. From what I have read there is a very good chance the UART functions are in use. I can not determine if that is the case nor can I feel confident I have disabled it. I would like to avoid rewriting to save on reprint a lot of PCBs and just rule out this UART bit all together. Would anyone be able to assist in this matter?
Re: disable the UART transmitter on the 88
Posted: Sat Apr 11, 2009 3:43 pm
by christian
The USART is disabled after reset. AVR-USB leaves it disabled unless you have turned on debugging.
Re: disable the UART transmitter on the 88
Posted: Sat Apr 11, 2009 8:58 pm
by ulao
And if I could, what would turn on the debug, the watch dog? My code has wdt_enable and wdt_reset called in a few spots.
Re: disable the UART transmitter on the 88
Posted: Sat Apr 11, 2009 9:10 pm
by christian
To enable debugging in AVR-USB, compile with -DDEBUG_LEVEL=1 or -DDEBUG_LEVEL=2. Debug output is sent to TxD at 19200 bps consisting primarily of hex dumps.
I would recommend to enable the watchdog only if everything else works.
Re: disable the UART transmitter on the 88
Posted: Sat Apr 11, 2009 9:34 pm
by ulao
thx christian, I appreciate it