2 xtc/2 serial communication with checksum, 3 xtc/2 serial communications - no checksum – INFICON XTC/3 Thin Film Deposition Controller Operating Manual User Manual
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XTC/3 Operating Manual
5.3.2 XTC/2 Serial Communication with Checksum
This portion of the protocol is in effect in addition to the portion described under
above if XTC/2 Ck Sum or XTC/C Ck Sum has been selected under
the RS-232 Protocol parameter.
ACK . . . . . . . Command acknowledged character, ASCII character value d06,
Control F from keyboard.
NAK . . . . . . . Command not acknowledged character, ASCII character value d21.
STX . . . . . . . Start of transmission character, ASCII character value d02
00,NN . . . . . . The size of the command is 2 bytes long with 00 representing the
high order Byte and NN representing the low order byte.
CS . . . . . . . . Checksum, modulo 256 value of message_string and ACK or NAK
To XTC: STX 00 NN message_string CS
From XTC: STX 00 NN ACK message_string CS (if success)
- or -
STX 00 NN NAK error code CS (if failure)
5.3.3 XTC/2 Serial Communications - No Checksum
This portion of the protocol is in effect in addition to the portion described under
above if XTC/2 No Ck Sum or XTC/C No Ck Sum has been selected
under the RS-232 Protocol parameter.
ACK . . . . . . . Command acknowledged character, ASCII character value d06,
Control F from keyboard.
NAK . . . . . . . Command not acknowledged character, ASCII character value d21.
To XTC: message_string ACK
From XTC: message_string ACK (if success)
- or -
error_code NAK (if failure)