Micromod Micro-DCI: 53IT5100A Indicator/Totalizer - Manual (Page 74)

B.1.6 SOFTWARE CHARACTERISTICS
1. Transparency Rule - whenever 7E hexadecimal is transmitted as anything other than
SOH, a 00 byte will be inserted directly following it (byte stuffing).
2. All transactions are initiated by the Host or SUPERVISOR-PC.
3. All instruments begin their response within 10 ms after the end of the transmission by
the Host or SUPERVISOR-PC; otherwise, a faulty transmission may be assumed.
4. Illegal messages received by the instruments are ignored.
5. The host must acknowledge the instrument’s response to a CHANGE REQUEST within
100 ms or the request is ignored.
6. A break of 100 ms in a message causes the instrument to ignore the part of the mes-
sage before the break.
7. The maximum number of data bytes per message is 32 (decimal).
B.1.7 HARDWARE CHARACTERISTICS
1. Transmission Speed - standard rates are 300 - 28800 baud.
2. Asynchronous by character.
3. A character is:
1 Start bit.
8 Data bits - the Least Significant Bit (LSB) is transmitted first.
1 Even Parity bit.
1 Stop bit.
4. Line is 4-wire, shielded twisted pair, type RS-422/485.
53IT5100 Indicator/Totalizer
B-8