[Coco] 6x09 instruction timings

[John Kowalski]

At 05:01 PM 20/01/2007 -0600, Joel Ewy wrote:
>I know that the Q clock and the E clock are 180 degrees out of phase,
>and that the CPU uses this relationship to separately clock different
>internal states.  But when reading instruction set timings, a cycle is
>one complete cycle of the E clock, without respect to what Q is doing
>(though their period is the same), is that correct?  So at 1.78 MHz, 1
>cycle of the E clock is a little more than .56 microseconds, if I
>understand this correctly.
>
>Just looking at Sockmaster's Hicolor code and thinking about how much
>processing could be done during the scan lines, vertical blanking, etc.

Instruction set timing is listed in complete cycles.  You never need to
worry or think about the E-Q cycle subdivisions at the software level.

The most important number to know when synchronizing code with video
scanlines is this (this applies to both CoCo 1/2 and 3):
At 1.79 Mhz there are 114 CPU cycles per scan line.
At 0.89 Mhz there are 57 CPU cycles per scan line.

                                         John Kowalski (Sock Master)
                                         http://www.axess.com/twilight/sock/