NDA-30115 Revision 1.0 Page 17
Property Management System - Communication Interface Architecture
Timers and
Counters Retransmission Counts
Timer Values
Table 2-9 Retransmission Counts
Meaning Count
The number of retransmissions of the start sequence when there is no
answer after transmitting the start sequence. 7
The number of retransmissions of the start sequence when NAK is
received after transmitting the start sequence. 7
The number of transmitting ENQs when WACK is received after the
transmission of an information block 15
The number of transmitting ENQs when there is no answer after the
transmission of an information block. (3 second intervals) 7
Table 2-10 Timer Values
Party Starting Condition Timer value
(seconds)
NEAX Waiting for a start sequence answer. 1
Waiting for STX after transmitting the start sequence ACK. 20
Waiting for data reception complete (waiting for ETX, CRC). 20
Waiting for an answer after the transmission of a message. 1
PMS Waiting for a start sequence answer. 3
Waiting for STX after transmitting the start sequence ACK. 25
Waiting for data reception complete (waiting for ETX, CRC). 25
Waiting for an answer after the transmission of a message. 3