[Vice-emu-mail] X64SC Monitor, chis, unaccounted clock cycles.

I am using x64sc 3.9 (GTK3 3.24.41, GLib 2.80.0, Cairo 1.18.0, Pango
1.52.1) which I'm pretty certain is compiled from source.


Last week, I used chis for the cpu_history and I noticed something
peculiar...

C:c402  A9 10       LDA #$10       A:0e X:6f Y:00 SP:d8 .V-..I.C
 191041395
.C:c404  9D 00 C0    STA $C000,X    A:10 X:6f Y:00 SP:d8 .V-..I.C
 191041397
.C:c083  48          PHA            A:10 X:6f Y:00 SP:d5 .V-..I.C
 191041452
.C:c084  AD 18 C0    LDA $C018      A:10 X:6f Y:00 SP:d4 .V-..I.C
 191041455
.C:c087  4A          LSR A          A:0e X:6f Y:00 SP:d4 .V-..I.C
 191041459

Does anyone know why the STA (9D) take 55 clock cycles?  From the MOS
datasheet, I see that it should be 5.  Is this a bug in the emulator or is
there something quirky with the C64 hardware that I don't know about yet?

Timothy Legg