L9663 datasheet(65/104 Pages) STMICROELECTRONICS

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L9663

Communication interface

103

DCR (PROG)

Direct Command Register

Address:

011110

Type:

Description:

A write operation on this register carries out specific actions, depending on the bits

written.

1) In order to perform a software reset of the L9663, the hexadecimal value 0x5555

("unlock reset" command) has first to be written into this register, followed by the

hexadecimal value 0xA5A5 ("reset" command) in the next SPI cycle. If this condition

is not met, no software reset will occur.

2) In order to reset the UDB1 (Upstream Data Buffer 1) for ECU-to-sensor

communication on the PSI5 channel 1, 0x00FF has to be written to this register. This

also resets the UDB1_RDY bit in the UDBCR register to 0.

3) In order to reset the UDB2 (Upstream Data Buffer 2) for ECU-to-sensor

communication on the PSI5 channel 2, 0xFF00 has to be written to this register. This

also resets the UDB2_RDY bit in the UDBCR register to 0.

4) Writing the hexadecimal value 0x1111 into this register locks the configuration

registers (EOP, End Of Programming), i.e. it is no longer possible to write the

configuration registers (marked with PROG). The PROG bit in the SPI Status bits is '0'

after the EOP command has been sent. This bit is reset to '1' at device reset (POR,

RESETN, SW_RESET or clock error).

5) If value 0x9999 is written into this register the writing of STS or STSR registers is

allowed. This is intended to grant a safety enabler for writing these couple of

registers. If value 0x9999 is written in PROG phase, then both STS and STSR

registers are allowed to be written, otherwise only STSR is allowed. To disable writing

these two registers, value 0x9090 has to be written here. The status of the

configuration (STS and STSR registers writeable or not) is shown with the STS_EN

bit in the SR3 register.

Default value:

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L9663 Datasheet(PDF) 65 Page - STMicroelectronics