| Description | Rear Power Distribution |
|---|---|
| Target release | MSXIV |
| Epic | |
| Document owner | |
| Project leads | Arshan Khanifar |
| Team members |
Goals
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Background and strategic fit
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CAN Communication
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Requirements
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Questions
| Question | Answer |
|---|---|
| How do you control the rear lights? | The lights are controlled by the GPIO pins of the MCP23008 I/O expanders. These I/O expanders are accessible over the I2C bus. The two which control the rear lights are address 0x20 and 0x22. The expander at 0x20 is used to set the diagnostic selection pins for the strobe light (GP1), rear brake lights (GP2), and rear turning lights (GP3) - active high. The expander at 0x22 is used to enable each of the rear lights (GP2-7) - active high. I/O Datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/MCP23008-MCP23S08-Data-Sheet-20001919F.pdf Power Switch Datasheet: https://www.infineon.com/dgdl/Infineon-BTS7200-2EPA-DS-v01_00-EN.pdf?fileId=5546d462636cc8fb016421e548a61215 |
| How to control the power of each board? | We can't control how much current each board draw, that is determined by the board's current action but we can turn the power going to the boards on and off, this is done by using the load switches. To turn on the load switch, an enable signal (high) need to be send to the load switch enable pin this allows the boards to get power. The controller board controls the load switch through I/O expanders explained on previous question. 2ch load switch: https://www.infineon.com/dgdl/Infineon-BTS7200-2EPA-DS-v01_00-EN.pdf?fileId=5546d462636cc8fb016421e548a61215 |
| What are the incoming CAN messages? | |
| What are the outgoing CAN messages? | |
| How do you manage power when the car turns on? | |
| How do you manage power when the car turns off? | |
| What is still powered when there's been a BMS fault? |