Easily irritated engineer of odd things
Joined:
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Posts:
30918
EE: 100% (5)
MN, USA
Posted: 12/8/2025 12:35:54 AM EDT
[Last Edit: Rat_Patrol][Edited]
Old Bobcat 440B. I'm sick as hell today, so writing code  . This project has been on my list for years. Wrote a program before I never put to PCB, but that was then, this is better. A version will also go on my 316 garden tractor, as the original 40 year old wiring is nothing but headaches anymore.Some of the features, always looking for ideas for more. ETA: Oh, the PCB will be all solid state, with resettable PCB fuses where needed. No relays to fail or burnout fuses to replace! That and the solid state high side drivers can be configured to a maximum current, so they act as their own "fuse". ----------------------------------------------- Keyless, child-resistant lockout Controller boots in a locked state and only accepts start requests after a deliberate unlock (PIN/chord), with clear "controller locked enter code" messaging. OFF, KEY_ON, CRANKING, RUNNING, STORAGE SHUTDOWN, FAULT, etc., so engine and power behavior are deterministic and easy to debug. Smart starter protection Crank timeouts, minimum pause between attempts, RPM-based lockout to avoid engaging the starter against a spinning engine. After crank-learn, a momentary start press runs the full crank attempt until the engine fires or times out. Waterproof servos replace mechanical linkages, with room for in-field calibration and temperature-aware choke/throttle behavior. Engine temperature based warmup protection A simple temperature band model (really cold / cold / warm) backed by a sensor: Cold engine 10 s idle lock (with elevated idle for really cold). Then 20% throttle cap until both: ~45 s of runtime has elapsed, and Engine is in the warm band. On-screen "warmup" toast so limited throttle is clearly intentional, not a fault. Hydraulic-friendly operation The warmup routine implicitly protects hydraulics from full-load abuse on a cold engine, and there's a hook for a future hydraulic oil level sensor. Idle shutdown to prevent extended idling Detects true idle (RPM + throttle + load) and shuts down after a configurable timeout to save fuel and reduce wear. Menu-driven "storage shutdown" that closes fuel, manipulates choke, and runs the carburetor dry under control instead of just killing power. Post-stop egress lighting logic If any utility light was on at stop: All configured light circuits stay on for 2 minutes with an "Egress Lighting XXs" display. If all were off, electronics stay alive only 5 seconds. Multi-circuit lighting with one button Up to three independently driven light outputs (front/rear/aux) with a single button cycling OFF front front+rear all OFF; number of circuits is software-configurable. Deep sleep with keypad wake After post-stop and key-on timers, the system requests deep sleep so only a small keypad rail remains awake, minimizing parasitic draw. Still has a mechanical switch to kill all power to the electronics for emergencies. Filtered fuel gauge with smooth bar display Fuel sender analog in is normalized, spike-clamped, and averaged to show a stable but responsive fuel bar on the display. Hour meter and maintenance hooks Integrated runtime tracking aimed at later adding service reminders and logs. Expandable hardware design Planned support for: I C expanders and sensors. Optional differential I C extenders. Optional CAN via SPI. Multiple power domains (3.3 V logic, 5 V optos, ~6 V servos) sized for real off-road use. |
Strong men create good times. Good times breed weak men. Weak men create hard times. (You are here) Hard times breed strong men.
Easily irritated engineer of odd things
Joined:
Jul 2008
Posts:
30919
EE: 100% (5)
MN, USA
|
Record a retrievable battery charge curve so you can predict when your battery is going bad? Would it be possible to have hydraulic pressure as part of the gauge package? Maybe with an alert if a sudden loss (or spike?!) of pressure is detected? |
01010111 | 57 | 127 | LXXXVII
Easily irritated engineer of odd things
Joined:
Jul 2008
Posts:
30933
EE: 100% (5)
MN, USA
|
Originally Posted By MongooseKY: Would it be possible to have hydraulic pressure as part of the gauge package? Maybe with an alert if a sudden loss (or spike?!) of pressure is detected? |
Strong men create good times. Good times breed weak men. Weak men create hard times. (You are here) Hard times breed strong men.
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