Rainbow Electronics AT73C502 User Manual
Page 14

AT73C500
14
The six data packages arrive as follows:
Figure 9. Data transfer to processor in six packages
In normal mode, the Sync LS byte indicates the number of
data package which will follow (value 0...5). There are also
two special situations indicated by this byte. Value six of
Sync LS byte means that the processor is expected to sup-
ply calibration data to AT73C500. Value seven is written by
AT73C500 in case power interruption is detected and bill-
ing information needs to be transferred to microprocessor.
In this case the processor knows that both packages 3 and
4 will follow one after each other as shown in Figure 10.
Table 5. Package 4
Byte
Data
Order
Meaning
1
Sync LS
Single byte
Synchronization
2
Sync MS
Single byte
Synchronization
3
Mode
Single byte
Mode information
4
Status
Single byte
Status information
5
REG15
(LS+2) byte
Reactive energy,
capacitive load
6
REG15
MS byte
Reactive energy,
capacitive load
7
REG15
LS byte
Reactive energy,
capacitive load
8
REG15
(LS+1) byte
Reactive energy,
capacitive load
9
REG16
(LS+2) byte
Counter
10
REG16
MS byte
Counter
11
REG16
LS byte
Counter
12
REG16
(LS+1) byte
Counter
13
REG17
LS byte
Frequency
14
REG17
MS byte
Frequency
15
REG18
LS byte
Reserved
16
REG18
MS byte
Reserved
Table 6. Package 5
Byte
Data
Order
Meaning
1
Sync LS
Single byte
Synchronization
2
Sync MS
Single byte
Synchronization
3
Mode
Single byte
Mode information
4
Status
Single byte
Status information
5
REG19
LS byte
Voltage, phase 1
6
REG19
MS byte
Voltage, phase 1
7
REG20
LS byte
Voltage, phase 2
8
REG20
MS byte
Voltage, phase 2
9
REG21
LS byte
Voltage, phase 3
10
REG21
MS byte
Voltage, phase 3
11
REG22
LS byte
Current, phase 1
12
REG22
MS byte
Current, phase 1
13
REG23
LS byte
Current, phase 2
14
REG23
MS byte
Current, phase 2
15
REG24
LS byte
Current, phase 3
16
REG24
MS byte
Current, phase 3
1
2
3
4
5
6
7
8
9
10
1
2
3
4
5
200ms = 655360 clocks @ 3.2768 MHz
20 ms
Pack
0
Pack
1
Pack
2
Pack
3
Pack
4
Pack
5
Pack
0
Pack
1
Pack
2
Pack
3
DATRDY
LINE PERIOD