[Coco] Instruction cycles per 60Hz frame.

[James Ross]

Looking for affirmation while trying to figure out the exact number of instruction cycles per 60Hz frame on the coco (where instructions take 2+ cycles each on the 6809).

This is what I am coming up with:

standard 60hz frame = 14914.7727272727 cycles per second
double speed 60hz frame = 29829.5454545455 cycles per second

does that look correct? 

thanks, 
James

PS: this is the C# code I used to calculate these:

double NTSC = 315d / 88d;
double coco_clk = NTSC / 4;
double double_speed = NTSC / 2;

double sixty_hz = 1d / 60d;
double ms_per_frame = sixty_hz * 1000;

double cycles_per_ms = coco_clk * 1000;
double cycles_per_60hz_frame = cycles_per_ms * ms_per_frame;

double double_cycles_per_ms = double_speed * 1000;
double double_cycles_per_60hz_frame = double_cycles_per_ms * ms_per_frame;

Console.WriteLine($"standard 60hz (vsync) frame = {cycles_per_60hz_frame} cycles per second");
Console.WriteLine($"double speed 60hz (vsync) frame = {double_cycles_per_60hz_frame} cycles per second");