Hi,
A normal servo has a 1-2ms pulse interval repeated every 20ms(more or less.)
The midpoint is at 1.5 ms.
If you make use of a microcontroller and its timer to generate a clock pulse every 4 us, you could make a counter with 255 divisions / steps between 1 and 2 ms. This would give you complete control of the position of the servo. In fact it's more than complete because the servo does not recognise all steps due to the mechanical lag.
127 pulses is more than enough, so if you increase the input clock period to 8 us, you could use a value from 128 to 255 for the variable pulse. This is about 1 to 2 ms pulse width interval. This is then repeated every 20 ms.
Hope I made some sense
TOK