INFICON STM-1 Thin Film Deposition Monitor - Manual (Page 3)

1. Hardware
1.1 Specifications:
Sensor Inputs: 1
Sensor Frequency: 1.95MHZ - 10.05MHZ
Frequency Accuracy (Absolute): <2ppm
Frequency Stability (Relative Accuracy) Nominal: .03HZ
Measurement Period: 100ms (Ten measurements per second, regardless of frequency).
Thickness Resolution:
.02 A
Rate (Raw) Resolution: .02 A/sec
Communication Electrical: RS232 or RS485 (dip-switch selectable), 9600 or 115200 BAUD (dip-switch selectable)
Communication Protocol: SMDP (Sycon Multi Drop Protocol)
1.2 Connections:
Electrical Connections at board (DB9 female connector):
Pin# Description
1
Analog output ground. NOT ISOLATED.
2 RS232 TxD/RS485 inverting (-)
3 RS232 RxD/RS485 non-inverting (+)
4 No connection
5 Communication signal gnd.
6 Analog output, 0 to +10V, 12 bits, nominal. 30 mA current source.
7 No connection
8 No connection
9 Alternate power (+5V) input if J2 is not used, 500 mA supply required.
RS232 PC to STM1 communication cable:
DB9 male pin# (plug into STM1)
Connect to DB9 FEMALE PIN# (plug into PC)
2 (STM1 TxD) 2 (PC RxD)
3 (STM1 RxD) 3 (PC TxD)
5 (STM1 GND) 5 (PC GND)
1.3 Dipswitch Settings:
On, or 1, is when the dipswitch is in the up position (top position when switch is viewed with switch labeled 1 on the left and
switch 8 on the right). Off, or 0, is when the dipswitch is in the down position.
Switch number
Controls Description
1 Nothing Unused
2 Endian Selection (see note 1.1) 0 = little endian (LS first)
1 = big endian (MS first), Default
3 Communication Checksum
(See note1.2)
0 = No checksum
1 = Checksum required, Default
4 Baud Rate 0 = 9600 Baud
1 = 115,200 Baud, Default
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