Revision 1.3

Mar.22 2001

-17-

GL646USB

The resolution of motor speed control is 16 bits, so, we can control vertical resolution

By one dpi increment, the resolution can be from 1 DPI to 4800DPI for 1200DPI scanner

And 1 DPI to 9600 DPI for 2400dpi scanner.

Note: The resolution of quarter step can up to four times resolution.

6.20. Acceleration/Deceleration Double Table

The acceleration/deceleration slope tables are store in DRAM, can be download by S/W.

The slope can be programmed by S/W for each table. Resolution is 16 bits pixel-time. The number of slope steps is

1~255 steps. One table is for scanning The other is for fast move.

The forward and backward steps can be programmed by S/W. The resolution is 16 bits pixel-time. The number of

slope steps is 1~255 steps. You can adjust any non-linear curve.

Note: what is fast move? Such as move back to go home or move to window any position to scan.

(1). Two table moving :

scan finished

buffer full position

Scanning position

Go to scan window

forward

backward

go home

time

speed

B

A

C

D

E

F

G

H

I

J

A,J

: table two (slope two) acceleration curve.

B

: table two (slope two) deceleration curve.

C,D,I : table one (slope one) acceleration curve.

E,F,H : table one (slope one) deceleration curve.

G

: touch home sensor deceleration curve.