Fix Amlogic S19j Pro runtime bring-up

README.md

@@ -206,7 +206,16 @@ running.
 
 That HB2 config now targets the corrected native mapping for hashboard 2:
 `/dev/ttyS1` with reset GPIO `456`, detect GPIO `441`, TMP75 addresses
-`0x4C/0x48`, and EEPROM address `0x50`.
+`0x4E/0x4A` on `/dev/i2c-1`, and EEPROM address `0x52` on `/dev/i2c-1`.
+
+The Amlogic configs also support a `startup.fan_control` PID loop. The current
+S19j Pro profiles enable it with a `60C` target and duty-cycle clamps so the
+board can regulate fan speed from the TMP75 readings instead of staying fixed
+at the startup PWM percentage.
+
+`/home/root/start.sh` now sources `/home/root/mujina.env` first when present,
+so pool credentials, API bind address, and log level can be adjusted without
+editing the wrapper itself. A template lives at [`mujina.env.example`](mujina.env.example).
 
 ### GT Touch USB Display
 

mujina-hb2.toml

@@ -15,6 +15,16 @@ psu_settle_ms = 2000
 reset_assert_ms = 100
 reset_release_ms = 2000
 
+[hardware.amlogic_control_board.startup.fan_control]
+enabled = true
+target_temp_c = 60.0
+min_percent = 35
+max_percent = 100
+kp = 3.0
+ki = 0.15
+kd = 8.0
+integral_limit = 200.0
+
 [hardware.amlogic_control_board.startup.health_gate]
 read_eeprom_before_mining = true
 read_temperatures_before_mining = true
@@ -65,8 +75,8 @@ model = "s19j_pro"
 serial_path = "/dev/ttyS1"
 reset_gpio = 456
 detect_gpio = 441
-temp_i2c_device = "/dev/i2c-0"
-temp_sensor_addresses = [76, 72]
-eeprom_i2c_device = "/dev/i2c-0"
-eeprom_address = 80
+temp_i2c_device = "/dev/i2c-1"
+temp_sensor_addresses = [78, 74]
+eeprom_i2c_device = "/dev/i2c-1"
+eeprom_address = 82
 required = true

mujina-miner/src/asic/bm13xx/thread_v2.rs

@@ -44,6 +44,25 @@ fn min_viable_chip_count(expected: usize) -> usize {
     expected / 2
 }
 
+fn configured_target_frequency() -> protocol::Frequency {
+    const DEFAULT_TARGET_FREQ_MHZ: f32 = 500.0;
+
+    match std::env::var("MUJINA_TARGET_FREQ_MHZ") {
+        Ok(raw) => match raw.parse::<f32>() {
+            Ok(mhz) if mhz.is_finite() && mhz > 0.0 => protocol::Frequency::from_mhz(mhz),
+            Ok(_) | Err(_) => {
+                warn!(
+                    value = %raw,
+                    default_mhz = DEFAULT_TARGET_FREQ_MHZ,
+                    "Invalid MUJINA_TARGET_FREQ_MHZ; using default"
+                );
+                protocol::Frequency::from_mhz(DEFAULT_TARGET_FREQ_MHZ)
+            }
+        },
+        Err(_) => protocol::Frequency::from_mhz(DEFAULT_TARGET_FREQ_MHZ),
+    }
+}
+
 /// [`HashThread`] implementation for BM13xx ASIC chains.
 ///
 /// The scheduler uses this to dispatch mining work to BM13xx chips.
@@ -663,8 +682,8 @@ where
         self.execute_reg_config_perchip().await?;
 
         // 7. Ramp frequency to target (flat voltage throughout)
-        self.execute_frequency_ramp(protocol::Frequency::from_mhz(500.0))
-            .await?;
+        let target_frequency = configured_target_frequency();
+        self.execute_frequency_ramp(target_frequency).await?;
 
         self.chip_state = ChipState::Initialized;
         let status = self.update_status(|status| {