Справочник Пользователя для Agrident Corporation ASR700
05.07.2007
Page 27 of 56
ASR700 Reader Operation
3. Operating
modes
The ASR700 supports three operating modes, which can be configured.
If changing the operation mode, the reader will not accept a mode change command until it has
finished processing/transmitting a response, (see chapter 5) any command it has already re-
ceived. Using bus systems (see chapter 2.3.6) avoid changing from slave modes (see chapter
3.1, 3.2) into master mode (see chapter 3.3) since this could result in data collisions on the
lines.
The data buffers are cleared when there is a change of operating mode.
If changing the operation mode, the reader will not accept a mode change command until it has
finished processing/transmitting a response, (see chapter 5) any command it has already re-
ceived. Using bus systems (see chapter 2.3.6) avoid changing from slave modes (see chapter
3.1, 3.2) into master mode (see chapter 3.3) since this could result in data collisions on the
lines.
The data buffers are cleared when there is a change of operating mode.
3.1 Operating in slave request mode (Cfg_mode register 0x02)
In slave request mode the read function is not activated until reception of a command
('Get_Single_ID'; for description see chapter 5.7.9) - in other words a request. The user soft-
ware on the control computer can look after controlling the read function. The ID message of an
acquired transponder is transmitted once in the appropriate format at the interface. After the de-
tection of a transponder and the transmission of the ID message – or after a timeout has
elapsed – the read function terminates. If a transponder is not detected before the timeout
elapses a blank ID message will be transmitted. Switching the RF field on and off is handled
automatically by the ASR700.
A fresh transmission of the 'Get_Single_ID' command causes the read procedure to be re-
peated.
When 'Get_Last_ID' is transmitted (see chapter 5.7.5) a new read cycle is not started but in-
stead the last registered transponder ID is transmitted.
In this mode the interface protocol is bi-directional. The control computer here functions as a
command transmitter and the reader as the responding partner. The receiver confirms com-
mands.
Note: In the case of a bus set-up using RS485 connection, data collision is possible on the bus
if several readers are addressed simultaneously with 'Get_Single_ID' or 'Get_Last_ID'.
Possible applications
Point-to-point connection with RS232/RS485: only one reader is connected by computer serial
interface.
Bus system with RS485: several readers are connected to a computer, configured with different
network addresses and are interrogated in sequence by the computer; for example,
('Get_Single_ID'; for description see chapter 5.7.9) - in other words a request. The user soft-
ware on the control computer can look after controlling the read function. The ID message of an
acquired transponder is transmitted once in the appropriate format at the interface. After the de-
tection of a transponder and the transmission of the ID message – or after a timeout has
elapsed – the read function terminates. If a transponder is not detected before the timeout
elapses a blank ID message will be transmitted. Switching the RF field on and off is handled
automatically by the ASR700.
A fresh transmission of the 'Get_Single_ID' command causes the read procedure to be re-
peated.
When 'Get_Last_ID' is transmitted (see chapter 5.7.5) a new read cycle is not started but in-
stead the last registered transponder ID is transmitted.
In this mode the interface protocol is bi-directional. The control computer here functions as a
command transmitter and the reader as the responding partner. The receiver confirms com-
mands.
Note: In the case of a bus set-up using RS485 connection, data collision is possible on the bus
if several readers are addressed simultaneously with 'Get_Single_ID' or 'Get_Last_ID'.
Possible applications
Point-to-point connection with RS232/RS485: only one reader is connected by computer serial
interface.
Bus system with RS485: several readers are connected to a computer, configured with different
network addresses and are interrogated in sequence by the computer; for example,
PC
"Get_Single_ID"
ASR700
Read function activated
Transponder detected
Read
function deactivated
"ID-Message"