I am using the rc522_spi to scan RF ID card to unlock a garden gate.
I can hold a list of valid tags in a global string, comma separated.
I also want the ability to add new valid tags…
I’ve decided to do this by having a special tag called “Add”. When this is presented to the reader, it signals that the next tag presented should be added to the valid tag global string.
The ISSUE:
How can I persist the valid tag global string so that should the ESP32 be switched off and on, the new tag is in the valid tag global string?
What I’ve tried:
text_sensor: moving the global string to a text_sensor - not allowed to have restore_mode: true, not allowed an initial value.
sensor: - doesn’t like strings
I even tried ChatGPT, but it gets this completely wrong suggesting restore_mode is available in options that are not possible.
Can anyone help?
Any pointers to web pages or documentation would be greatly appreciated.
Whole code pasted below. Sorry if it’s a bit rough 
In the past, I implemented all of this in Home Assistant. But when that is offline, the gate lock becomes unoperable. I’d like this gate to be usable at all times.
Many thanks in advance
esphome:
name: rfid32
comment: RFID Gate Controller
area: Garden
friendly_name: rfid32
on_boot:
- priority: 600 # Ensures it runs after other boot tasks
then:
- delay: 5s # Wait for 5 seconds
- lock.lock: lock1
esp32:
board: esp32dev
framework:
type: arduino
# Enable logging
logger:
# Enable Home Assistant API
api:
encryption:
key: "ABCDE/0FGHIJKLMNOPQRSTUVWXYZabcdefghijklmno="
substitutions:
device_name: rfid32
ota:
- platform: esphome
password: "password"
preferences:
flash_write_interval: 1s
wifi:
ssid: !secret wifi_ssid
password: !secret wifi_password
# Enable fallback hotspot (captive portal) in case wifi connection fails
ap:
ssid: "Rfid32 Fallback Hotspot"
password: "password"
captive_portal:
spi:
clk_pin: GPIO18
mosi_pin: GPIO23
miso_pin: GPIO19
button:
- platform: safe_mode
name: Safe Mode
id: ${device_name}_safe_mode
icon: mdi:restart-alert
device_class: restart
entity_category: diagnostic
disabled_by_default: true
interval:
- interval: 60s
then:
- if:
condition:
wifi.connected:
#api.connected:
then:
- lambda: |-
ESP_LOGI("watchdog", "wifi.connected");
else:
- lambda: |-
ESP_LOGW("watchdog", "considering safe_mode");
- delay: 60s
- if:
condition:
#api.connected:
wifi.connected:
then:
- lambda: |-
ESP_LOGI("watchdog", "wifi.connected");
else:
- lambda: |-
ESP_LOGE("watchdog", "entering safe_mode");
- button.press: ${device_name}_safe_mode
rc522_spi:
cs_pin: GPIO21
reset_pin: GPIO22
update_interval: 0.25s
on_tag:
then:
- lambda: |-
id(rfid_text_sensor).publish_state(x.c_str());
ESP_LOGI("main", "Value of sensor %s", id(rfid_text_sensor).state.c_str());
if (id(id_valid_tags).find(id(rfid_text_sensor).state.c_str()) != std::string::npos) {
ESP_LOGI("main", "Value of valid tag is %s", id(rfid_text_sensor).state.c_str());
id(valid_card).publish_state(true); //Match found
id(add_next_card_switch).turn_off();
} else {
ESP_LOGI("main", "******INVALID TAG******");
ESP_LOGI("main", "INVALID: %s", id(rfid_text_sensor).state.c_str());
ESP_LOGI("main", "CLEAR : %s", id(id_clear).c_str());
ESP_LOGI("main", "ADD : %s", id(id_add).c_str());
id(valid_card).publish_state(false); //No Match
ESP_LOGI("main","ADD State: %d", id(add_next_card_switch).state);
if (id(rfid_text_sensor).state == id(id_clear)) {
ESP_LOGI("main", "CLEAR MEMORY REQUESTED %s", id(rfid_text_sensor).state.c_str());
id(id_valid_tags) = "";
id(add_next_card_switch).turn_off();
} else {
if (id(rfid_text_sensor).state == id(id_add)) {
ESP_LOGI("main", "ADD TAG REQUESTED %s", id(rfid_text_sensor).state.c_str());
id(add_next_card_switch).publish_state(true);
} else {
if (id(add_next_card_switch).state) {
ESP_LOGI("main", "ADDING CARD %s", id(rfid_text_sensor).state.c_str());
id(id_valid_tags) = id(id_valid_tags) + "!" + id(rfid_text_sensor).state;
}
id(add_next_card_switch).turn_off();
}
}
}
ESP_LOGI("main", "Valid tags from ***STORAGE*** are %s", id(id_valid_tags).c_str());
on_tag_removed:
then:
- lambda: |-
id(rfid_text_sensor).publish_state("");
ESP_LOGI("main", "Value of sensor %s", id(rfid_text_sensor).state.c_str());
id(valid_card).publish_state(false); //Clear Match
text_sensor:
- platform: template
name: "Scanning Tag"
id: rfid_text_sensor
- platform: wifi_info
ip_address:
name: ESP IP Address
address_0:
name: ESP IP Address 0
address_1:
name: ESP IP Address 1
address_2:
name: ESP IP Address 2
address_3:
name: ESP IP Address 3
address_4:
name: ESP IP Address 4
ssid:
name: ESP Connected SSID
bssid:
name: ESP Connected BSSID
mac_address:
name: ESP Mac Wifi Address
scan_results:
name: ESP Latest Scan Results
dns_address:
name: ESP DNS Address
binary_sensor:
- platform: status
name: "RFID status"
- platform: template
name: "Valid card"
id: valid_card
device_class: occupancy
on_press:
then:
- lock.unlock: lock1
- delay: 5s
- lock.lock: lock1
- platform: gpio
pin:
number: GPIO35
name: "RFID button"
on_press:
then:
- lock.unlock: lock1
- delay: 5s
- lock.lock: lock1
- platform: rc522
uid: C7-EB-0F-29
name: "Clear"
- platform: rc522
uid: 44-96-E3-72
name: "Add"
- platform: rc522
uid: 99-84-17-55
name: "George"
- platform: rc522
uid: B9-1C-17-55
name: "Zippy"
sensor:
- platform: wifi_signal
name: "RFID522 WiFi Signal"
update_interval: 60s
switch:
- platform: restart
name: "RFID restart"
- platform: template
name: "Add next card"
id: add_next_card_switch
optimistic: true
restore_mode: RESTORE_DEFAULT_OFF
light:
- platform: binary
id: blue_light
name: "Blue LED"
output: blue_led
output:
- platform: gpio
id: relay
pin:
number: GPIO0
inverted: false
- platform: gpio
id: blue_led
pin: GPIO2
lock:
- platform: output
name: "Garden Gate Lock"
id: lock1
output: relay
on_lock:
- logger.log: "Door Locked!"
- light.turn_off: blue_light
on_unlock:
- logger.log: "Door Unlocked!"
- light.turn_on: blue_light
globals:
- id: id_clear
type: std::string
initial_value: '"C7-EB-0F-29"'
- id: id_add
type: std::string
initial_value: '"44-96-E3-72"'
- id: id_valid_tags
type: std::string
initial_value: '"!99-84-17-55!B9-1C-17-55"'
- id: id_names
type: std::string
initial_value: '"!George !Zippy "'