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2) TRANSMISSION PROCEDURE
(1) PD-II sends data to External Device whenever weight is changed after receiving <W> signal
from the External Device.
(2) PD-II stops sending data when receives <CR> signal from the External Device.
External Device
<W> ------
----- DATA (If weight is changed)
------ DATA (If weight is changed)
<CR> ------ Stop transmitting data
3.1.3. TYPE-0 and TYPE-1 INTERFACE
Most P.O.S Systems, ECRs and some TEC P.O.S Systems.
1) PROTOCOL
EXTERNAL DEVICE SCALE(PD-II)
<ENQ> ------------ Initiate communication
<DC2> ------------ Request of weight data
------------ <ACK> : Acknowledge the request of weight data
Inquiry
------------ <STX> : Start Transmission
------------ <ID> : Scale type identifier
------------ <W5> : Weight data
------------ <W4> : Weight data
------------ <W3> : Weight data
------------ <W2> : Weight data
------------ <W1> : Weight data
------------ <BCC> : Block Check Character
------------ <ETX> : End Transmission