Determining Red vs Green Light for Lightning Board State

[dnakhooda]

Description
On boot, we want to wait for messages from the BMS and IMD saying they are ready. Once we get those two messages, we want to send messages to the lightning board using send_lightning_board_light_status. If Cerberus determines there is a critical fault, we send LIGHT_RED. If there is no fault, we send LIGHT_GREEN.

Proposed Solution

1. Read boot messages from BMS and IMD
2. Read fault information from Cerberus
3. Send either LIGHT_RED or LIGHT_GREEN

[bjackson312006]

@Sara1025-2006 Ok this ticket is no longer blocked, so it's good to be worked on.

Here's some more info about the ticket:
Basically, we need code to use send_lightning_board_light_status() to set the state of the lightning board light. There are three states: LIGHT_OFF, LIGHT_RED, and LIGHT_GREEN. The state of the light should correspond to these conditions:

1. At startup: LIGHT_OFF
2. If either BMS or IMD are faulted: LIGHT_RED
3. Otherwise: LIGHT_GREEN

This is probably how I would go about implementing this:

1. At initialization time, set the light to LIGHT_OFF. Probably do this in lightning_init(), or somewhere else if you find a better place
2. Then probably in the shutdown thread, check the states of bms_gpio and imd_gpio. If either indicates a fault, set the light to LIGHT_RED. Otherwise, set the light to LIGHT_GREEN.

Let me know if you have any questions!