Wiki¶

There are some issues that can only be tested via power resets.

• SPI has an issue that it needs retries
• Looks like configuration I2C EEPROM gets reset to defaults
• RTC-offline-test (Wie lange haelt die RTC Batterie)

The device has an CANBus in and an CANBus out. The testsoftware is on the DUT. The DUT sends the command to toggle power line to Awaria via CAN.
The switch-off time has to be an parameter. The RTC-Tests will be complex, the Awaria software shall be simple and generic.

An data multiplexer can be used along with a mosfet for power line.
Data lines for CAN and UART have to be cut.
In order to cut UART, an Debug-Adapter chaining would be needed. Or Uart is available via Host-USB.

Optionally controll it via USB from PC, not MCU. Optically isolated GPIOs.

Problem¶

Circuit does not help at all when power is injected into device via Pullup of RS232. Lines can be disabled too. But whole
debug connector can cause issues: No debug connection at all.
FPC with UART only? All signals disconnectable?

Usecases¶

• Devices have their own test-software and ask awaria to perform an power-cycle for them. Result is stored in option Bytes.
• PC performs test. DUT has to send Log-Events when errors show up and when device is up and running. DUT firmware can be the productive firmware.
  • Tester-Firmware on PC is quite generic
  • CAN may not be available yet (CANDis). That was one intention of repeated log code
  • CANDis may be configured to use USB. No UART output here. USB does also not help then.

Parts¶

• MCU: The smallest thing
• Multiplexer:
  • MC14551BDG bis zu 1K RON: 1050
  • TS5A23166DCUR cool, 2 channels, up to 100mA, 1,8-6,5V
  • Habe:
    • DG408LEDQ-T1-GE3; .#273; 1:8
    • DG409LEDQ-T1-GE3; .#321; 2x 1:4
    • ADG736; .#315; 2x1:2
    • RS2102XN ADG836YRMZ Das ist er; 2x
  • MAX4760; 8 Channels; Paarweise schalten
  • TMUX1574 4xSPDT; 1 Schalter
  • PI5C3257QE; 4xSPDT; 1 Schalter; 0.229€

• Big EEPROM, device can store test info from DUT

Spannungs/Strom zu umstaendlich.

RTC-Tests¶

Can have a region in SPI-Flash.
If the Settings are not ok, just have an terminal.
The test can only be started from terminal.
rebootTest <startTime>

Start.

• Cut 2 Seconds. Time OK?
• Cut 4 Seconds. Time OK?
• Cut 8 Seconds. Time OK?

When it fails, "destroy" test-config in spi flash

Connectors¶

• CANBus-In
• CANBus.Out
• Power in
• Power out
• USB PC to MCU
• USB PC to DUT

Debug, CAN, power only?
CAN-Geraete koennten auch standalone laufen, Testsoftware auf PC.

2x Uart
2x SWD
1x Reset
1x Boot0
2x CAN
(DEBUG: VDD_5VIN, GND, VDD_TGT, SWO)

USB schalten is overkill, andere Platine.