APGRD003 Microchip Technology, APGRD003 Datasheet - Page 16

• Manufacturer Part Number: APGRD003
• Description: KIT TPMS REFERENCE DESIGN
• Manufacturer: Microchip Technology
• Type: Automotive, Tire Pressure Monitorr

Specifications of APGRD003

• Frequency: 433.92MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: PIC18F4680, PIC18F2680, MCP2030
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

DS51624B-page 12
3.2.6
The Base Station schedules when each tire is polled. The Base Station transmits the
command to wake up the Transponder Sensor module to each LF Initiators individually
on the LIN network. The command issued to LF Initiator contains a unique ID that was
pre-assigned to each Initiator. This command will be issued maximum of three times if
the previous attempt failed. The LF Initiator transmits a wake up command containing
the two bytes of data from the base station to the Transponder Sensor module. The
Base Station will then wait for an incoming RF data message stream from the
Transponder Sensor module which will also contain the LF Initiator ID to distinguish the
tire position.
FIGURE 3-1:
When the Learn Button (S1) is pressed, the Base Station places a Learn Mode ID in
the second data byte of the message. The Base Station then issues the learn command
sequentially to each LF initiator which in turn, transmits the command to the Transpon-
der Sensor module. The Base Station waits for the Transponder Sensor to transmit
back a message via UHF (the number of LF Initiators on the LIN network will determine
how many messages to be expected by the Base Station and this must be defined by
the user in the firmware). After a predetermined time has expired, an error message is
displayed on the LCD if all the expected messages are not received.
Operation Overview
Synch
Break
LIN MESSAGE COMMAND
Header
Synch
Field
Message Frame
Ident
Field
response space
in-frame
Position Mode Checksum
ID
Data
ID
Field
© 2006 Microchip Technology Inc.
inter-frame
or BREAK
space