MX8000 Installation and Operation Guide
8–28
8.8.7 System
Messages
The character $01 at the beginning of a data string indicates that the MX8000 is reporting its internal
status. A sample system message is shown in Figure 8–15. Table 8–28 lists the possible system messages
and what format the data can take.
$01 $30 $36 $32 $37 $39 $34 $22 $30 $33 $34 $35 $22 $7A $39 $30 $30 $30 $63 $OD
Separator
Separator
Date
Time
Separator
System Message Data
(Battery Restore)
V=Byte
End Of Message
Indicator
Figure 8–15: System Message
Table 8–28 lists the system messages. Some system messages are one byte. Other messages are always sent
with other information, such as the line card number. All system messages are sent separately. For example,
if two line cards have a problem at the same time, the MX8000 will send one message for each LinePort. The
V-Byte and a carriage return ($0D) always follow system messages.
Table 8–28: System Messages
SYSTEM MESSAGE
MEANING
(PRINTED MESSAGE)
$77
AC LOST
$78 AC
RESTORE
$7B COMPUTER
TROUBLE
$7D COMPUTER
RESTORE
$70 + 2 bytes for line card number
LINE CARD TROUBLE
$72 + 2 bytes for line card number
LINE CARD TRBL RSTR
$71 + 2 bytes for line number
PHONE LINE TROUBLE
$73 + 2 bytes for line number
PHONE LINE RESTORE
$79 + 4 bytes indicating MX8000. (See
Note below.)
BATTERY TROUBLE
MX8000
$7A + 4 bytes indicating MX8000.
BATTERY RESTORE
MX8000
$7F + 2 bytes indicating the
number of the
log on code (not the code itself).
LOG ON OPERATOR
$7E + 2 bytes indicating the
number of the
log off code (not the code itself).
LOG OFF OPERATOR
Note:
The 4 bytes are the ASCII coded values for the model numbers “MX8000”. For example, “$79 $39 $38
$30 $30” means “battery trouble with MX8000”.
8.8.8 Communication from a Computer to the MX8000
8.8.8.1 ACKing and NACKing Data
The computer must respond to messages sent by the MX8000 with an ACK or NACK.
An ACK ($06) is sent when the computer’s V-Byte calculation agrees with the V-Byte value sent in the
message and the general format of the message looks correct (for example, the last byte was $0D).
A NACK ($15) is sent whenever the computer suspects an error in the transmission of the message. The
computer must respond within one timeout period of receiving the last byte of a message. (See
Ack Time
(Acknowledge Time) on page 5–19
)