I was asked this question and I didn't really know the answer....
AT THE CARTRIDGE CONNECTOR, I was asked this question:
What frequency, duty cycle, and logic level (TTL [5v], LVTTL [3.3v], other)?
Logic level I know is 5v
Frequency I assume is 21.47727 MHz. IS this correct (at the cart connector)?
Duty Cycle??????
Thanks
Mark
http://wiki.nesdev.com/w/index.php/Cartridge_connectorWhat signal would you want to know the duty of? Because I'm pretty sure there's the clock..R/W pin...and that's it?
Duty cycle of the clock. Not sure why it wouldn't be 50%. Puzzled as to why this would be relevant. Maybe if one was probing around and identifying the line not by its physical location, but merely the signal on it.
3gengames wrote:
http://wiki.nesdev.com/w/index.php/Cartridge_connector
What signal would you want to know the duty of? Because I'm pretty sure there's the clock..R/W pin...and that's it?
?NES clock the same as SNES?
A friend was wanting to use the clock signal as a reference for an external timer. So I wasn't sure if the clk freq was the same on the cartridge connector as the rest of the system.
Ah, I'm too used to NES development, hah. But this page has that info:
http://wiki.superfamicom.org/snes/show/ ... 26+Pinouts
CPU_CLOCK (Super NES Game Pak pin 57, which corresponds to Famicom/NES M2) might not be 50% duty when the CPU is accessing slow memory.