sl-firmware 7785a16bff feat: Battery voltage telemetry and LVC (Issue #613)
- Add include/lvc.h + src/lvc.c: 3-stage low voltage cutoff state machine
  WARNING  21.0V: MELODY_LOW_BATTERY buzzer, full motor power
  CRITICAL 19.8V: double-beep every 10s, 50% motor power scaling
  CUTOFF   18.6V: MELODY_ERROR one-shot, motors disabled + latched
  200mV hysteresis on recovery; CUTOFF latched until reboot
- Add JLINK_TLM_LVC (0x8B, 4 bytes): voltage_mv, percent, protection_state
  jlink_send_lvc_tlm() frame encoder in jlink.c
- Wire into main.c:
  lvc_init() at startup; lvc_tick() each 1kHz loop tick
  lvc_is_cutoff() triggers safety_arm_cancel + balance_disarm + motor_driver_estop
  lvc_get_power_scale() applied to ESC speed command (100/50/0%)
  1Hz JLINK_TLM_LVC telemetry with fuel-gauge percent field
- Add LVC thresholds to config.h (LVC_WARNING/CRITICAL/CUTOFF/HYSTERESIS_MV)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-03-15 11:04:38 -04:00

40 lines
1.3 KiB
C

#ifndef LVC_H
#define LVC_H
#include <stdint.h>
#include <stdbool.h>
/*
* lvc.h -- Low Voltage Cutoff (LVC) protection (Issue #613)
*
* 3-stage battery voltage protection using battery_read_mv():
*
* LVC_WARNING (21.0 V) -- periodic buzzer alert; full power maintained
* LVC_CRITICAL (19.8 V) -- faster buzzer; motor commands scaled to 50%
* LVC_CUTOFF (18.6 V) -- error buzzer; motors disabled; latched until reboot
*
* Recovery uses LVC_HYSTERESIS_MV to prevent threshold chatter.
* CUTOFF is one-way: once latched, only a power-cycle clears it.
*
* Integration:
* lvc_init() -- call once during system init
* lvc_tick(now_ms, vbat_mv) -- call each main loop tick (1 kHz)
* lvc_get_power_scale() -- returns 0/50/100; apply to motor speed
* lvc_is_cutoff() -- true when motors must be disabled
*/
typedef enum {
LVC_NORMAL = 0, /* Vbat >= WARNING threshold */
LVC_WARNING = 1, /* Vbat < 21.0 V -- alert only */
LVC_CRITICAL = 2, /* Vbat < 19.8 V -- 50% power */
LVC_CUTOFF = 3, /* Vbat < 18.6 V -- motors off */
} LvcState;
void lvc_init(void);
void lvc_tick(uint32_t now_ms, uint32_t vbat_mv);
LvcState lvc_get_state(void);
uint8_t lvc_get_power_scale(void); /* 100 = full, 50 = critical, 0 = cutoff */
bool lvc_is_cutoff(void);
#endif /* LVC_H */