User's Guide

17
Arad Technologies Ltd. | st. HaMada, Yokneam Elite , 2069206, Israel | www.arad.co.il
5.11 Open quite detection timer
5.11.1 When reader clock is received, a Quite Detection timer is opened.
5.11.2 When there are no clock events for 200ms, the system goes to power down mode.
5.12 Detect reader type
5.12.1 First 3 clock events are used for clock detection type.
5.12.2 The detection is done by the measuring the frequency of the Reader’s clock.
5.12.3 The clock frequency for 2w reader is: 20 kHz - 30 kHz.
5.12.4 The clock frequency for 3w reader is less than 2 kHz.
5.13 Open timer for TPSL detection
5.13.1 When 2w reader is detected, a timer is opened for detection of TPSL time of quite
before transmitting each byte.
5.13.2 In 2w reader's protocol, each bit is transmitted in interval or quite.
5.14 Wait for down clock event, shift data out
• In 2w connection. After TPSL time is detected the bit is transmitted according to 2w
protocol.
'0' is transmitted as pulse of 50 kHz for 300 µs
'1' is transmitted as '0' for 300 µs
• In 3w connection. After TPOR time of delay the bit is transmitted according to 3w
protocol.
'0' is transmitted as '1'
'1' is transmitted as '0'
Each bit is transmitted after clock down event.
5.15 Advance TX events counter, go to TRR
After each message transmission, the counter of TX events is updated. The counter is used for
indicating battery access exceed error when number of readings exceed battery access value.
After each transmission, for TRR time, the system is not receiving reader's clock events.
5.16 Message format/ Encoder configuration
Message from meter to Encoder:
Header
Addr
[7:6]
Type
[5:0]
Len
Data
End
Get Encoder Access
55
X
12
0
Null
CSum
Get Encoder Status
55
X
13
0
Null
CSum
Clear Encoder Status
55
X
14
0
Null
CSum
Encoder Data
55
X
15
4-10
Byte
Meter Data
CSum
1-4
5
6-9
Meter volume
(singed Int)
Alarm
Flow (float)
Encoder
Configuration
55
X
16
Error! Reference
source not found.
CSum
Len – data length; CSum - check sum over all frame [55...Data] or AA.