JAJSP77A November 2019 – August 2020 BQ79600-Q1
PRODUCTION DATA
To properly communicate to every device in daisy chain, host has to assign a unique device address to every device. This process is called Auto-addressing. This step is required every time devices come out of SHUTDOWN or digital reset. Table 7-9 describes a procedure to bring up a system of 1 bridge device and 3 stack devices from SHUTDOWN to a state ready to do read/write communication.
STEP | WORK WITH BQ7961X-Q1 | |
---|---|---|
1 | send WAKE ping on RX (wakeup BQ79600-Q1) | |
2 | single device write to BQ79600-Q1 CONTROL1 [SEND_WAKE] = 1 (wake up stack devices) | |
3 | dummy stack write data 0x00 to register 0x343 to 0x34A (sync up internal DLL). These are 8 separate write commands. | |
4 | brdcast write 0x01 to address 0x309 (enable auto addressing) | |
5 | brdcast write consecutively to 0x306 = 0,1,2,3 (address 1-3 assigned to BQ7961X-Q1, 0 assigned to BQ79600-Q1) | |
6 | brdcast write 0x02 to address 0x308 (set BQ7961X-Q1 as stack device ) | |
7 | single device write to device 3: data 0x03 to address 0x308 (set 3rd BQ7961X-Q1 as top of stack, BQ79600-Q1 is default to base) | |
8 | dummy stack read registers 0x343 to 0x34A (sync up internal DLL). These are 8 separate read commands. | |
9 | stack read address 0x306 (read back to verify address are correct for stack devices) | |
10 | single device read to BQ79600-Q1, verify 0x2001 = 0x14 | |
11 | finish initialization |