29
“Serial # query”
frame format – the data display system to the detecting unit
D7 D6 D5 D4 D3 D2 D1 D0
0
1
0
1
0
1
0
1 Byte 55h
–
start-of-frame character
Byte AAh
1
0
1
0
1
0
1
0
0
1
0
1
А3
А2
А1
А0
D7…D4 –
“Serial
#
query”
frame code
D3…D0 –
detecting unit address *
* -
0Fh
address – broadcast address. All detecting units respond to the query with such address.
“Serial #”
frame format – the detecting unit to the data display system
D7 D6 D5 D4 D3 D2 D1 D0
0
1
0
1
0
1
0
1 Byte 55h
–
start-of-frame character
Byte AAh
1
0
1
0
1
0
1
0
0
1
0
1
А3
А2
А1
А0
D7…D4 –
“Serial
#
”
frame code
D3…D0 –
detecting unit address *
Serial No._0 (low byte)
Serial No. of the detecting unit
Serial No._1
Serial No._2
Serial No._3 (high byte)
control
arithmetical checksum with a carry
“Address change”
frame format – the data display system to the detecting unit
D7 D6 D5 D4 D3 D2 D1 D0
0
1
0
1
0
1
0
1 Byte 55h
–
start-of-frame character
Byte AAh
1
0
1
0
1
0
1
0
0
1
1
0
А3
А2
А1
А0
D7…D4 –
“Address change”
frame code
D3…D0 –
current address of the detecting
unit
0
0
0
0
NА3
NА2
NА1
NА0
D3…D0 –
new address of the detecting unit
control
arithmetical checksum with a carry
“Confirmation”
frame format –the detecting unit to the data display system
D7 D6 D5 D4 D3 D2 D1 D0
0
1
0
1
0
1
0
1 Byte 55h
–
start-of-frame character
Byte AAh
1
0
1
0
1
0
1
0
1/0 0
1
1
А3
А2
А1
А0
D7 = 0
–
normal operation
D7 = 1
–
error
D6…D4 –
“Confirm
ation
”
frame code
D3…D0 –
OLD address of the detecting
unit
