Step pulses

We wish to clock our scan pixels to motor drive steps on the MM-3000. The required pulses are not normally available to the user, but you can steal them from the guts of the unit. You should remove the back panel from the MM-3000, and pull out the motor sine/cosine card for the axis of interest (it has four red LEDs on its top edge for the four motor phases). The connector on the front panel side of that card has the motor step pulses. The pulses go from that connector to a HCPL 2531 chip at position ICU1 on the driver board. We number the connector pins starting with 1 at the big square solder pad. The signals of interest are shown in Table 10.4.

Table 10.4: Connections to see the step pulses on the Newport MM-3000 motor controller/driver units.

Connector pin #	2531 pin #	DB9 pin #	Function
18		1	+5V
31		2	ground
12	2	3	X +step
11	3	4	X -step
12	2	5	Y +step
11	3	6	Y -step