[avr-chat] 16Mhz or bust

[Mikey Sklar]

I have been working with a ATmega32 through a stk500 under Mac OS/X.
I've had no trouble getting a little test serial program working through
the USART using the 1MHz default internal oscillator. However, I have
had no luck working at running the MCU at higher speeds than 1MHz.

I'm sure someone must have been successful using a AT part at greater
than 1MHz. What am I missing here?

Knobs I've been frobing with: 
  (note: these settings are known **BAD!**)

- Configuring the ATmega32 for 16MHz
  * stk500 - external 16MHz crystal installed
  * stk500 - XTAL1 unjumpered
  * stk500 - OSCSEL - pins 2,3 jumperred
  * Fuse high byte - CKOPT - 10011001 (uisp --wr_fuse_h=0x99)
  * Fuse low byte - CKSEL - 11101111 (uisp --wr_fuse_l=0xEF)
  * OSCCAL --wr_osc=16000000 (sets to 3686400, perhaps unsigned int  issue)
  * src code - 16MHz @ 2400bps UBRRL=432 or UBRRL=1B0

I've been using 'uisp' to set the fuse bits. I see at least one issue
with uisp not taking a clock value over 3.6864Mhz. I'm aware of the
usual mistakes:

- Internal oscillator maxes at 8MHz
- Fuse bits are inversed logic (0 is enabled)