https://uwmidsun.atlassian.net/browse/MH-152
J1772 Interface
- When board is powered, Regulator U3 should output 5V otherwise the PP and CP readings may be off.
- Y1 should output a 16MHz wave otherwise CAN may not work as expected.
In case documentation and instructions here are not clear enough, see this link: https://blog.digital-scurf.org/posts/evse-tester-prototype/ (unfinished but better than most stuff on the internet)Proximity Pilot (PP)
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“Parallel resistance” refers to the resistors + switch on pin 5 on the connector side.
Expected readings:
EVSE_PROXIMITY Voltage Parallel Resistance (VOhms) | U4 Inverting Input Voltage (V) | PA7 Voltage (V) |
|---|---|---|
Not Connected (infinite) | 4.46 | 2.735 |
480 | 12.5377 | 1.530.938 |
2.771502 | 1.7753 | 10.938 |
- PA7 should always be DC. Time constant for RC filter (R8, C10) = 10us = 100kHz
- PA7 should never exceed 3.3V
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