M10 Drives

• Control of the two low frequency M10 tilt motions, required for output pupil position adjustment. Control of the Dual Feed mirrors (when implemented) for output pupil position adjustment as well as reference object selection and tracking.
  
• The control is deployed on the Azimuth LCU.
• The device is connected to a RS232 port via connector W22.
  The two axes are driven by one OEM070 controller each. The two controllers are daisy-chained on the communication link.
  The two controllers are located in the ROS and switched OFF when not in use for reduced heat dissipation

The protocol is described in OEM070 User Guide (see Annex 1, p. 23ff. of [RD 03]). The contractor is responsible for the bootstrap procedure, to be burned in EPROM. The a angle is managed by the controller #1, while the b angle from the controller #2.

The conversion between encoder counts (after quadrature interpolation) and radians (or degrees) is given by a formula, given by the contractor.

M10 interfaces:

The connection layout and pin assignment of W22 and Z18 is given in Annex 1 VLT-DWG-ESO-15154-1770

Item	From	To	Signal	Description	Pin
COMMUNICATION:
1			M10 Communication	RS232 Port - Protocol ASCII 9600 baud, 8 data bits, 1 stop bit, no parity	W22
TILTING:  M10 Unit conversion formulae in annex
10	LCU	ATS	Set M10 absolute (a,b) tilt angles	Sets absolute M10 tilt angles (a,b) in encoder counts (two separate commands, one per axis)	Software Command to W22
11	LCU	ATS	Set M10 relative (a,b) tilt angles	Sets relative M10 tilt angles (a,b) in encoder counts (two separate commands, one per axis)
12	ATS	LCU	Get M10 absolute (a,b) tilt angles	Gets absolute M10 tilt angles (a,b) in encoder counts (two separate commands, one per axis)
CONTROLLER:
20	LCU	ATS	Power On +	24VDC, 500mA supply to relay coil
21	LCU	ATS	Power On -	return

Last modified: Monday, 03/05/2001