Preparations for dedicated configuration flash page

.gitignore

@@ -4,3 +4,6 @@
 
 # Vim swap files
 .*.sw?
+
+# generated config HEX files
+utils/*.hex

Makefile

@@ -32,7 +32,7 @@ LDFLAGS+=--static \
          -nostartfiles -Wl,--gc-sections \
          -mthumb -mcpu=cortex-m0 -mthumb -mfloat-abi=soft
 
-# the LD script
+# the LD script (RAM-only does not work because the code is too large)
 #LDFLAGS+=-Tldscripts/lnsc-2420-$(BUILD).ld
 LDFLAGS+=-Tldscripts/lnsc-2420-release.ld
 

ldscripts/lnsc-2420-debug.ld

@@ -7,6 +7,7 @@
 MEMORY
 {
 	/*rom (rx) : ORIGIN = 0x08000000, LENGTH = 64K*/
+	conf (r)  : ORIGIN = 0x08007c00, LENGTH = 1K
 	ram (rwx) : ORIGIN = 0x20000000, LENGTH = 4K
 }
 
@@ -96,6 +97,10 @@ SECTIONS
 
 	. = ALIGN(4);
 	end = .;
+
+	.conf : {
+		__conf_start = .;
+	} >conf
 }
 
 PROVIDE(_stack = ORIGIN(ram) + LENGTH(ram));

ldscripts/lnsc-2420-release.ld

@@ -3,10 +3,18 @@
 /* Define memory regions. */
 MEMORY
 {
-	rom (rx)  : ORIGIN = 0x08000000, LENGTH = 32K
+	rom (rx)  : ORIGIN = 0x08000000, LENGTH = 31K
+	conf (r)  : ORIGIN = 0x08007c00, LENGTH = 1K
 	ram (rwx) : ORIGIN = 0x20000000, LENGTH = 4K
 }
 
 /* Include the common ld script. */
 INCLUDE cortex-m-generic.ld
 
+SECTIONS
+{
+	.conf : {
+		__conf_start = .;
+		. = ALIGN(4);
+	} >conf
+}

src/flash_config.h

@@ -0,0 +1,117 @@
+#ifndef FLASH_CONFIG_H
+#define FLASH_CONFIG_H
+
+#include <stdint.h>
+
+extern uint8_t __conf_start;
+
+#define FLASH_CONFIG_BASE_PTR  ((uint8_t*)(&__conf_start))
+
+/***** Calibration factors *****/
+
+/* Calibration factor defined here are divided by 1000 to determine the actual
+ * scaling factor. Therefore, if the voltage determined by the firmware is 2%
+ * lower than the actual voltage, you have to scale by 1.02 and therefore
+ * specify 1020 in this list. */
+
+#define FLASH_CONFIG_CAL_FACTOR_U_BAT   (*(uint16_t*)(FLASH_CONFIG_BASE_PTR + 0x0000))
+#define FLASH_CONFIG_CAL_FACTOR_U_SOLAR (*(uint16_t*)(FLASH_CONFIG_BASE_PTR + 0x0002))
+#define FLASH_CONFIG_CAL_FACTOR_U_SW    (*(uint16_t*)(FLASH_CONFIG_BASE_PTR + 0x0004))
+#define FLASH_CONFIG_CAL_FACTOR_I_SOLAR (*(uint16_t*)(FLASH_CONFIG_BASE_PTR + 0x0006))
+#define FLASH_CONFIG_CAL_FACTOR_I_LOAD  (*(uint16_t*)(FLASH_CONFIG_BASE_PTR + 0x0008))
+
+/***** General configuration *****/
+
+/* Battery regulation corridor width (in mV). */
+#define FLASH_CONFIG_U_BAT_REGULATION_CORRIDOR (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0100))
+
+/* Initial charge battery voltage threshold (in mV). */
+#define FLASH_CONFIG_U_BAT_INITIAL_FULL (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0104))
+
+/* Cancel initial charge voltage hold below this battery voltage (in mV). */
+#define FLASH_CONFIG_U_BAT_INITIAL_HOLD_CANCEL (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0108))
+
+/* Transition to floating voltage levels after this time (in ms). */
+#define FLASH_CONFIG_INITIAL_CHARGE_HOLD_TIME (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x010C))
+
+/* Duration of the transistion from initial charging to float (in ms). */
+#define FLASH_CONFIG_INITIAL_TO_FLOAT_TRANSITION_TIME (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0110))
+
+/* Float charge battery voltage threshold (in mV). */
+#define FLASH_CONFIG_U_BAT_FLOAT_FULL (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0114))
+
+/* Minimum voltage difference to U_bat that the solar panels must produce
+ * before charging is resumed after it was switched off (in mV). */
+#define FLASH_CONFIG_SLEEP_SOLAR_EXCESS_VOLTAGE (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0118))
+
+/* Minimum charge current required before charging is stopped to save power at
+ * the charge pump (in mA). */
+#define FLASH_CONFIG_SLEEP_SOLAR_CURRENT (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x011C))
+
+/* Delay between state change and sleep state check (in ms). */
+#define FLASH_CONFIG_SLEEP_STATE_DELAY (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0120))
+
+/* Delay between charging switch state change and sleep state check(in ms). */
+#define FLASH_CONFIG_SLEEP_SWITCH_DELAY (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0124))
+
+/* Maximum allowed microcontroller temperature (in units of 0.1 °C). If this
+ * temperature is exceeded, charging is stopped. The load is kept on. Do not
+ * set this too high as the heat has to propagate from the power MOSFETs. */
+#define FLASH_CONFIG_INTERNAL_TEMPERATURE_LIMIT (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0128))
+
+/* Resume operation below this temperature (in units of 0.1 °C). */
+#define FLASH_CONFIG_INTERNAL_TEMPERATURE_RECOVERY (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x012C))
+
+
+/* Thresholds for load control */
+
+/* Voltage above which the load is turned on (in mV). */
+#define FLASH_CONFIG_U_BAT_LOAD_ON (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0130))
+/* Voltage below which the load is turned off (in mV). */
+#define FLASH_CONFIG_U_BAT_LOAD_OFF (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0134))
+
+/* Current at which the overload protection triggers (in mA). */
+#define FLASH_CONFIG_LOAD_CURRENT_LIMIT_MA (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0138))
+
+/* Inrush tolerance time (in ms). Overload protection is not enforced for this
+ * time after load power-on. */
+#define FLASH_CONFIG_LOAD_CURRENT_INRUSH_TIME (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x013C))
+
+/* Minimum voltage that the charge pump must produce above U_bat before any
+ * power FET is switched on (in mV). */
+#define FLASH_CONFIG_MIN_CHARGE_PUMP_EXCESS_VOLTAGE (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0140))
+
+/* The minimum time the load must be off before it can be switched on again (in ms). */
+#define FLASH_CONFIG_LOAD_ON_DELAY (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0144))
+
+
+/* Measurement Averaging:
+ * Alpha is specified in units of 1/1000. 1000 means that only the latest
+ * value is relevant, 0 means that the measurement has no influence. The latter
+ * is useless.
+ *
+ * The formula to calculate the next averaged value avg from a measurement meas is:
+ * avg[k] = meas * (alpha/1000) + avg[k-1] * (1 - alpha/1000)
+ *
+ * For overload protection (battery voltage, load current), the latest values
+ * are always used.
+ * */
+
+/* Averaging factor for load current. */
+#define FLASH_CONFIG_AVG_ALPHA_I_SOLAR (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0148))
+#define FLASH_CONFIG_AVG_ALPHA_I_LOAD (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x014C))
+#define FLASH_CONFIG_AVG_ALPHA_U_BAT (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0150))
+#define FLASH_CONFIG_AVG_ALPHA_U_SW (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0154))
+#define FLASH_CONFIG_AVG_ALPHA_U_SOLAR (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0158))
+#define FLASH_CONFIG_AVG_ALPHA_TEMP (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x015C))
+
+
+/* Generic configuration */
+
+/* Time (in ms) to stay active in idle state before entering deep sleep. */
+#define FLASH_CONFIG_DEEPSLEEP_DELAY (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0160))
+
+/* Deep sleep duration (in seconds). */
+#define FLASH_CONFIG_DEEPSLEEP_DURATION (*(uint32_t*)(FLASH_CONFIG_BASE_PTR + 0x0164))
+
+#endif // FLASH_CONFIG_H

utils/config_b26.yaml

@@ -0,0 +1,108 @@
+# Values for the device at the B26 tower
+
+calibration:
+  # Calibration factor defined here are divided by 1000 to determine the actual
+  # scaling factor. Therefore, if the voltage determined by the firmware is 2%
+  # lower than the actual voltage, you have to scale by 1.02 and therefore
+  # specify 1020 in this list.
+  CAL_FACTOR_U_BAT:      994
+  CAL_FACTOR_U_SOLAR:    997
+  CAL_FACTOR_U_SW:       996
+  CAL_FACTOR_I_SOLAR:   1015
+  CAL_FACTOR_I_LOAD:    1000
+
+config:
+  # Thresholds for charging control
+
+  # Battery regulation corridor width (in mV).
+  U_BAT_REGULATION_CORRIDOR: 100
+
+  # Initial charge battery voltage threshold (in mV).
+  # stop charging if battery voltage reaches this threshold
+  U_BAT_INITIAL_FULL: 28600
+
+  # Cancel initial charge voltage hold below this battery voltage (in mV).
+  U_BAT_INITIAL_HOLD_CANCEL: 27000
+
+  # Transition to floating voltage levels after this time (in ms).
+  INITIAL_CHARGE_HOLD_TIME: 1800000
+
+  # Duration of the transistion from initial charging to float (in ms).
+  INITIAL_TO_FLOAT_TRANSITION_TIME: 600000
+
+  # Float charge battery voltage threshold (in mV).
+  # stop charging if battery voltage reaches this threshold
+  U_BAT_FLOAT_FULL: 27600
+
+  # Minimum voltage difference to U_bat that the solar panels must produce
+  # before charging is resumed after it was switched off (in mV).
+  SLEEP_SOLAR_EXCESS_VOLTAGE: 1000
+
+  # Minimum charge current required before charging is stopped to save power at
+  # the charge pump (in mA).
+  SLEEP_SOLAR_CURRENT: 1
+
+  # Delay between state change and sleep state check (in ms).
+  SLEEP_STATE_DELAY: 60000
+
+  # Delay between charging switch state change and sleep state check(in ms).
+  SLEEP_SWITCH_DELAY: 1000
+
+  # Maximum allowed microcontroller temperature (in units of 0.1 °C). If this
+  # temperature is exceeded, charging is stopped. The load is kept on. Do not
+  # set this too high as the heat has to propagate from the power MOSFETs.
+  INTERNAL_TEMPERATURE_LIMIT: 500
+
+  # Resume operation below this temperature (in units of 0.1 °C).
+  INTERNAL_TEMPERATURE_RECOVERY: 450
+
+
+  # Thresholds for load control
+
+  # Voltage above which the load is turned on (in mV).
+  U_BAT_LOAD_ON: 27000
+  # Voltage below which the load is turned off (in mV).
+  U_BAT_LOAD_OFF: 24000
+
+  # Current at which the overload protection triggers (in mA).
+  LOAD_CURRENT_LIMIT_MA: 10000
+
+  # Inrush tolerance time (in ms). Overload protection is not enforced for this
+  # time after load power-on.
+  LOAD_CURRENT_INRUSH_TIME: 10
+
+  # Minimum voltage that the charge pump must produce above U_bat before any
+  # power FET is switched on (in mV).
+  MIN_CHARGE_PUMP_EXCESS_VOLTAGE: 10000
+
+  # The minimum time the load must be off before it can be switched on again (in ms).
+  LOAD_ON_DELAY: 10000
+
+
+  # Measurement Averaging:
+  # Alpha is specified in units of 1/1000. 1000 means that only the latest
+  # value is relevant, 0 means that the measurement has no influence. The latter
+  # is useless.
+  #
+  # The formula to calculate the next averaged value avg from a measurement meas is:
+  # avg[k] = meas * (alpha/1000) + avg[k-1] * (1 alpha/1000)
+  #
+  # For overload protection (battery voltage, load current), the latest values
+  # are always used.
+
+  # Averaging factor for load current.
+  AVG_ALPHA_I_SOLAR: 10
+  AVG_ALPHA_I_LOAD: 10
+  AVG_ALPHA_U_BAT: 100
+  AVG_ALPHA_U_SW: 100
+  AVG_ALPHA_U_SOLAR: 100
+  AVG_ALPHA_TEMP: 10
+
+
+  # Generic configuration
+
+  # Time (in ms) to stay active in idle state before entering deep sleep.
+  DEEPSLEEP_DELAY: 1000
+
+  # Deep sleep duration (in seconds).
+  DEEPSLEEP_DURATION: 10

utils/config_dev.yaml

@@ -0,0 +1,108 @@
+# Values for the development device
+
+calibration:
+  # Calibration factor defined here are divided by 1000 to determine the actual
+  # scaling factor. Therefore, if the voltage determined by the firmware is 2%
+  # lower than the actual voltage, you have to scale by 1.02 and therefore
+  # specify 1020 in this list.
+  CAL_FACTOR_U_BAT:     1012
+  CAL_FACTOR_U_SOLAR:   1015
+  CAL_FACTOR_U_SW:      1006
+  CAL_FACTOR_I_SOLAR:   3980
+  CAL_FACTOR_I_LOAD:    1000
+
+config:
+  # Thresholds for charging control
+
+  # Battery regulation corridor width (in mV).
+  U_BAT_REGULATION_CORRIDOR: 100
+
+  # Initial charge battery voltage threshold (in mV).
+  # stop charging if battery voltage reaches this threshold
+  U_BAT_INITIAL_FULL: 28600
+
+  # Cancel initial charge voltage hold below this battery voltage (in mV).
+  U_BAT_INITIAL_HOLD_CANCEL: 27000
+
+  # Transition to floating voltage levels after this time (in ms).
+  INITIAL_CHARGE_HOLD_TIME: 1800000
+
+  # Duration of the transistion from initial charging to float (in ms).
+  INITIAL_TO_FLOAT_TRANSITION_TIME: 600000
+
+  # Float charge battery voltage threshold (in mV).
+  # stop charging if battery voltage reaches this threshold
+  U_BAT_FLOAT_FULL: 27600
+
+  # Minimum voltage difference to U_bat that the solar panels must produce
+  # before charging is resumed after it was switched off (in mV).
+  SLEEP_SOLAR_EXCESS_VOLTAGE: 1000
+
+  # Minimum charge current required before charging is stopped to save power at
+  # the charge pump (in mA).
+  SLEEP_SOLAR_CURRENT: 1
+
+  # Delay between state change and sleep state check (in ms).
+  SLEEP_STATE_DELAY: 60000
+
+  # Delay between charging switch state change and sleep state check(in ms).
+  SLEEP_SWITCH_DELAY: 1000
+
+  # Maximum allowed microcontroller temperature (in units of 0.1 °C). If this
+  # temperature is exceeded, charging is stopped. The load is kept on. Do not
+  # set this too high as the heat has to propagate from the power MOSFETs.
+  INTERNAL_TEMPERATURE_LIMIT: 500
+
+  # Resume operation below this temperature (in units of 0.1 °C).
+  INTERNAL_TEMPERATURE_RECOVERY: 450
+
+
+  # Thresholds for load control
+
+  # Voltage above which the load is turned on (in mV).
+  U_BAT_LOAD_ON: 27000
+  # Voltage below which the load is turned off (in mV).
+  U_BAT_LOAD_OFF: 24000
+
+  # Current at which the overload protection triggers (in mA).
+  LOAD_CURRENT_LIMIT_MA: 10000
+
+  # Inrush tolerance time (in ms). Overload protection is not enforced for this
+  # time after load power-on.
+  LOAD_CURRENT_INRUSH_TIME: 10
+
+  # Minimum voltage that the charge pump must produce above U_bat before any
+  # power FET is switched on (in mV).
+  MIN_CHARGE_PUMP_EXCESS_VOLTAGE: 10000
+
+  # The minimum time the load must be off before it can be switched on again (in ms).
+  LOAD_ON_DELAY: 10000
+
+
+  # Measurement Averaging:
+  # Alpha is specified in units of 1/1000. 1000 means that only the latest
+  # value is relevant, 0 means that the measurement has no influence. The latter
+  # is useless.
+  #
+  # The formula to calculate the next averaged value avg from a measurement meas is:
+  # avg[k] = meas * (alpha/1000) + avg[k-1] * (1 alpha/1000)
+  #
+  # For overload protection (battery voltage, load current), the latest values
+  # are always used.
+
+  # Averaging factor for load current.
+  AVG_ALPHA_I_SOLAR: 10
+  AVG_ALPHA_I_LOAD: 10
+  AVG_ALPHA_U_BAT: 100
+  AVG_ALPHA_U_SW: 100
+  AVG_ALPHA_U_SOLAR: 100
+  AVG_ALPHA_TEMP: 10
+
+
+  # Generic configuration
+
+  # Time (in ms) to stay active in idle state before entering deep sleep.
+  DEEPSLEEP_DELAY: 1000
+
+  # Deep sleep duration (in seconds).
+  DEEPSLEEP_DURATION: 10

utils/config_to_hex.py

@@ -0,0 +1,69 @@
+#!/usr/bin/env python3
+
+import sys
+import struct
+
+import yaml
+from intelhex import IntelHex
+
+BASE_ADDR = 0x08007C00
+
+CALIBRATION_KEY_TO_OFFSET = {
+        "CAL_FACTOR_U_BAT":   0x0000,
+        "CAL_FACTOR_U_SOLAR": 0x0002,
+        "CAL_FACTOR_U_SW":    0x0004,
+        "CAL_FACTOR_I_SOLAR": 0x0006,
+        "CAL_FACTOR_I_LOAD":  0x0008,
+    }
+
+CONFIG_KEY_TO_OFFSET = {
+        "U_BAT_REGULATION_CORRIDOR":        0x0100,
+        "U_BAT_INITIAL_FULL":               0x0104,
+        "U_BAT_INITIAL_HOLD_CANCEL":        0x0108,
+        "INITIAL_CHARGE_HOLD_TIME":         0x010C,
+        "INITIAL_TO_FLOAT_TRANSITION_TIME": 0x0110,
+        "U_BAT_FLOAT_FULL":                 0x0114,
+        "SLEEP_SOLAR_EXCESS_VOLTAGE":       0x0118,
+        "SLEEP_SOLAR_CURRENT":              0x011C,
+        "SLEEP_STATE_DELAY":                0x0120,
+        "SLEEP_SWITCH_DELAY":               0x0124,
+        "INTERNAL_TEMPERATURE_LIMIT":       0x0128,
+        "INTERNAL_TEMPERATURE_RECOVERY":    0x012C,
+        "U_BAT_LOAD_ON":                    0x0130,
+        "U_BAT_LOAD_OFF":                   0x0134,
+        "LOAD_CURRENT_LIMIT_MA":            0x0138,
+        "LOAD_CURRENT_INRUSH_TIME":         0x013C,
+        "MIN_CHARGE_PUMP_EXCESS_VOLTAGE":   0x0140,
+        "LOAD_ON_DELAY":                    0x0144,
+        "AVG_ALPHA_I_SOLAR":                0x0148,
+        "AVG_ALPHA_I_LOAD":                 0x014C,
+        "AVG_ALPHA_U_BAT":                  0x0150,
+        "AVG_ALPHA_U_SW":                   0x0154,
+        "AVG_ALPHA_U_SOLAR":                0x0158,
+        "AVG_ALPHA_TEMP":                   0x015C,
+        "DEEPSLEEP_DELAY":                  0x0160,
+        "DEEPSLEEP_DURATION":               0x0164,
+    }
+
+
+if __name__ == "__main__":
+    output = IntelHex()
+
+    if len(sys.argv) < 3:
+        print(f"usage: {sys.argv[0]} <yaml-config> <output-hex>")
+        sys.exit(1)
+
+    with open(sys.argv[1], 'r') as configfile:
+        config = yaml.safe_load(configfile)
+
+    for key, offset in CALIBRATION_KEY_TO_OFFSET.items():
+        value = config['calibration'][key]
+        enc_bytes = struct.pack('<H', value)
+        output.puts(BASE_ADDR + offset, enc_bytes)
+
+    for key, offset in CONFIG_KEY_TO_OFFSET.items():
+        value = config['config'][key]
+        enc_bytes = struct.pack('<I', value)
+        output.puts(BASE_ADDR + offset, enc_bytes)
+
+    output.write_hex_file(sys.argv[2])