IMBRIOS LOGSENS_V1P1

ESP32-based environmental sensing board - designed for data logging and remote monitoring systems.

Micro-USB
IMBRIOS LOGSENS_V1P1 board
ESP32
MCU
240MHz
clock
4MB
flash
520KB
SRAM
23· 7 ADC
GPIO
BLE 4.2+ WiFi
radio
On this page

Pinout

25 pins
View:
PinGPIOLabelsStatusCapabilitiesNotes
10SW2_BUILDINstrapping-
21TXPWMuartuart
32A12T2PWMstrappingadc · touch
43RXPWMuartuart
54UART2_RTSCAN_TXDEPWMstrapping-
612MISOPWMstrappingspi
713MOSIPWMstrappingspi
814SCKPWMstrappingspi
915SSA13T3PWMstrappingadc · touch · spi
1016UART2_RXCAN_RXPWMstrapping-
1117UART2_TXCAN_TXPWMstrapping-
1219BUZZER_CTRLPWMsafe-
1321SDAPWMsafei2c
1422SCLPWMsafei2c
1523SPI_SS1PWMsafe-
1625A18DAC1PWMsafeadc · dac
1726A19DAC2PWMsafeadc · dac
1827A17T7PWMsafeadc · touch
1932A4T9PWMsafeadc · touch
2033LED_BUILTINA5T8PWMsafeadc · touch
2134SW4_BUILDINstrapping-
2235SD_CARD_DETECTstrapping-
2336SW3_BUILDINstrapping-
24-LED1_BUILDINsafe-
25-LED2_BUILDINsafe-

Start with these

9 pins with no boot or system involvement
BUZZER_CTRLPWMSDAPWMSCLPWMSPI_SS1PWMA18DAC1A19DAC2A17T7A4T9LED_BUILTINA5

Freely assignable - no strapping, flash, USB or JTAG duties. Ideal first picks for buttons, sensors and LEDs.

Fine - with a little care

sampled at boot or shared with debug/serial
PinLabelWhat to knowRole
SW2_BUILDINGPIO0Must be HIGH during boot for normal startup; if held LOW on reset, forces flash programming mode.Strapping
A12GPIO2If driven HIGH on reset (while IO0 is LOW), selects an unsupported SDIO boot mode, causing boot failure.Strapping
UART2_RTSGPIO4Sampled at reset for boot config; should not be driven at boot (affects boot mode timing).Strapping
MISOMTDI (GPIO12)Keep LOW during boot (internal PD); pulling HIGH at reset selects 1.8V flash mode, causing flash brownout if 3.3V flash is used.Strapping
MOSIMTCK (GPIO13)Used for JTAG debugging (TCK); avoid using as GPIO if JTAG is needed.Other
SCKMTMS (GPIO14)Used for JTAG debugging (TMS); driving it as GPIO may interfere with JTAG or produce spurious signals at boot.Other
SSMTDO (GPIO15)Keep HIGH during boot (internal PU); if LOW on reset, bootloader log is silenced and boot mode may change.Strapping
SW4_BUILDINGPIO34Cannot be used as output (no drive capability); only suitable for analog/digital input.Other
SD_CARD_DETECTGPIO35Cannot be used as output; only suitable for input.Other
SW3_BUILDINGPIO36 (SENSOR_VP)Cannot be used as output; only suitable for input (e.g., analog read).Other

Only if you know the tricks

wired to flash or USB - expect a fight
PinLabelWhat to knowRole
TXU0TXD (GPIO1)Connected to on-board USB-UART for uploading and logs; drives serial output at boot, so using as GPIO can disrupt programming or console.USB
RXU0RXD (GPIO3)Used for receiving data from USB-UART (programming); also pulled HIGH at boot for console communication, so using as GPIO can disrupt uploads.USB
UART2_RXGPIO16Connected to internal PSRAM on PSRAM-enabled modules; not usable as GPIO on those modules.Flash
UART2_TXGPIO17Connected to internal PSRAM on PSRAM-enabled modules; not usable as GPIO on those modules.Flash
These are recommendations, not hard rules - with the right pull-ups, timing and boot-state awareness most pins can be made to work. When in doubt, start green.
Pinout notes The IMBRIOS LOGSENS_V1P1 breaks out 25 pins in total: 23 GPIO for your project. For peripherals, I²C is mapped to SDA on GPIO21 and SCL on GPIO22; the SPI bus…

The IMBRIOS LOGSENS_V1P1 breaks out 25 pins in total: 23 GPIO for your project.

For peripherals, I²C is mapped to SDA on GPIO21 and SCL on GPIO22; the SPI bus (MOSI, MISO, SCK, SS) is broken out in full; TX/RX on GPIO1 and GPIO3 cover serial logging and flashing.

On the analog side there are 7 ADC-capable pins for sensors and battery monitoring, 5 capacitive-touch inputs and 2 true DAC outputs.

If you want zero surprises, BUZZER_CTRL, SDA, SCL, SPI_SS1 and 5 more are free of any such role - the safest first picks. 10 of the exposed pins carry boot-time or system duties on the ESP32 (SW2_BUILDIN, A12, UART2_RTS and 7 more).

Getting started

flash your first firmware in ~2 minutes
Tool:
1
Connect over USB
Install your USB-serial driver (CH340 / CP210x) if no port appears. Not detected? Hold BOOT while plugging in.
2
Match & flash
Set the Tools options shown, then click Upload.
3
Verify it runs
The onboard LED on GPIO19 blinks - swap the pin if your board's LED differs.
Set these in Tools · leave everything else at default
Arduino IDE 2.x — Tools Copy
Board: "ESP32 Dev Module"
Flash Size: "4MB (32Mb)"
Flash Mode: "DIO"
Partition Scheme: "Default 4MB with spiffs (1.2MB APP / 1.5MB SPIFFS)" (default)
Upload Speed: "921600"
▸ every other Tools option — leave at default
Board: ESP32 Dev Module
Flash Size: 4MB (32Mb)
Flash Mode: DIO
Partition Scheme: Default 4MB with spiffs (1.2MB APP / 1.5MB SPIFFS)
Upload Speed: 921600
Find it: Tools ▸ Board ▸ ESP32 Arduino ▸ ESP32 Dev Module
blink.ino Copy
// blink the onboard LED
void setup() {
  pinMode(19, OUTPUT);
}
void loop() {
  digitalWrite(19, HIGH); delay(500);
  digitalWrite(19, LOW);  delay(500);
}
board to selectesp32dev⧉ copy
platformio.ini Copy
[env:imbrios-logsens-v1p1]
platform = espressif32
board = esp32dev
framework = arduino
monitor_speed = 115200
upload_speed = 921600
Find it: PlatformIO Home ▸ Boards, search esp32dev — or type it after board =.
board to selectesp32dev⧉ copy
device.yaml Copy
esp32:
  board: esp32dev
  variant: imbrios-logsens-v1p1
  framework:
    type: esp-idf

# blink - GPIO19
output:
  - platform: gpio
    pin: 19
    id: led_out
light:
  - platform: binary
    name: "LED"
    output: led_out
Find it: search ESPHome's board list for esp32dev (same ids as PlatformIO).
esptool doesn't pick board settings — a prebuilt .bin already has them baked in. This is just the raw flash command.
terminal Copy
esptool.py --chip esp32 --port /dev/ttyACM0 \
  --baud 921600 write_flash 0x0 firmware.bin
--port = your /dev/tty* (macOS/Linux) or COMx (Windows).
Build details: sketch space 1310720 B · data 327680 B · DIO

Specifications

ESP32
Compute
MCU
ESP32
Clock
240 MHz
SRAM · Flash
520 KB · 4MB
Radio
Wi-Fi
802.11 b/g/n
Bluetooth
4.2 LE
Antenna
PCB
I/O
GPIO · ADC
23 · 7
UART · I²C · SPI
3 · 2 · 4
PWM
16 channels
Power
USB
Micro-USB
Serial
-
Boot address
0x1000
Flashing
Upload · OTA
esptool_py · esp_ota
Flash · Boot mode
DIO · DIO
Sketch · Data
1.25 MB · 320 KB
The IMBRIOS LOGSENS_V1P1 uses esptool_py for firmware uploads, esp_ota for over-the-air (OTA) updates. Flash mode is DIO with DIO boot mode. The maximum sketch size is 1.25 MB with 320 KB available for data.

About this board

At its core is the ESP32 - a dual-core Xtensa with both Bluetooth Classic and BLE.

Onboard you'll find a microSD slot, a Grove connector, an RTC, a buzzer, an RS485 interface and a CAN bus interface.

Resources

Similar boards