Assembly file created in Atmel Studio and flashed on Atmega16 on Pinboard2 Rev 2. It used one of the atmega timers, and port d to supply data into 7seg display. It is important to note, that in original solution frequency of 8MHz was used and on gas version I will try to change it to 1Mhz. 8bit Timer/Counter1 was used.
I plan to port this code from atmel studio to
traditional emacs unix (OpenBSD) environment + plus switch to lower frequency
of MCU.
| File | Description |
| main.asm | File from Atmel studio |
OCR1A — output control register for timer counter 1.
| freq | dec | hex | fusebits (xHL) |
| 8 Mhz | 31250 | 0x7A12 | 0xE4D9 |
| 2 Mhz | 7813 | 0x1E85 | 0xE2D9 |
| 1 Mhz | 3907 | 0x0C19 | 0xE1D9 |
How to calculate:
- 256 / freq = x
- 1 / x = res
- Round and convert to hex
avrdude -c avrftdi -p m16 -P usb -Ulfuse:w:0xE1:m -U hfuse:w:0xD9:m
Calculated with fuse-calc.
avrdude -c avrftdi -p m16 -P usb -U flash:w:file:a
This command is from windows AVRDUDESS.
On OpenBSD see /usr/local/share/doc/pkg_reamdes/avrdude
for info on flashing.