CCS/TPS92661-Q1: How to read the Diagnostic register for Status messages for Open and short LEDs, I need an example.

Hello Guarav,

This is the response I received, I hope it helps.

Regards,

Clint

"It is all explained in the spec. To me the sample the user should key in on is “Uint8 lmm_rd_1_reg(Uint8 lmm, Uint8 regaddr)”. Where the argument “regaddr” is either E0, E1 or E2. Once he has the data he wants he can parse it using the spec as well on page 30.

7.4.13.8 Diagnostic Registers

The diagnostic registers hold the results of various faults and status flags for the system. The diagnostic registers

exist in the address range E0h to E2h.

ADDR REGISTER D7 D6 D5 D4 D3 D2 D1 D0 DEFAULT

E0h FAULTL FAULT[8:1] 00000000

E1h FAULTH RESERVED FAULT[12:9] 00000000

E2h CERRCNT CERRCNT[7:0] 00000000

FAULT[12:1]: Fault Register

0 = an LED fault has not occurred

1 = an LED fault has occurred

The LED open and short fault detection circuitry is sampled just before the corresponding bypass switch

is closed. If a fault exists at this time instant, a 1 is latched into the associated FAULT register bit. The

FAULT register bits must be cleared manually by writing them back to 0. If an LED fault condition still

exists at the next PWM period, the device immediately resets the corresponding FAULT register bit to a

1. Writing the FAULT register bits to 1 has no effect.

CERRCNT[7:0]: CRC Error Count Register

This register value is incremented each time a CRC error is received. This register may be read by the

MCU and then written back to 0 to clear the count. The CERRCNT value saturates at FFh; it does not

wrap back to 0 when it reaches FFh. The CERRCNT register is not automatically cleared when a

communications reset is received. It must be cleared manually by writing it back to 0. Note that the

CERRCNT register can be written to any 8-bit value. This is intended for diagnostic purposes."