Festival Carousel Horse LED Controller Schematic

Work done
  • Completed the remaining schematic updates: replaced the RS-485 placeholder with U5 MAX485CSA+, powered it from 5V, wired UART/control nets, corrected DMX polarity labels to DMX_PLUS / DMX_MINUS, and updated the battery monitor divider to R32=10kΩ / R33=3.3kΩ.
  • Verified OLED is on 3V3 with I2C_SDA / I2C_SCL, dual XLR connectors are wired in parallel, and the user-input nets remain present for the 11 pots, 5 illuminated pushbuttons, and 4 toggles including LOW_BATT_OVERRIDE.
  • Updated the project notes with the four-block organization and full GPIO/signal assignment table: Carousel Horse LED Controller Design Notes.
Success criteria review
  • ✅ User inputs implemented and documented.
  • ✅ Comms/display updates completed, including MAX485, OLED, DMX XLRs, and monitor inputs.
  • ✅ ALL_CAPS net labels used for the updated/significant nets.
  • ✅ GPIO assignment table added to project notes.
  • ✅ ERC check reports no ERROR or WARNING items.
Next steps
  • The schematic is complete; next I can proceed to PCB layout cleanup/placement for the newly replaced MAX485 and then routing/manufacturing checks.
Organize placement
Run layout DRC
Export revision files
Check BOM availability
SW1
U4
U10
U9
OLED1
U8
U1
U7
R32 P2 - R33 P1
J11 Negative - J12 Negative
U5 ~RE~ - U1 GPIO32
VR8 WIPER - C19 P1
RV1 CW - VR1 CW
GND
U5 DI - U1 GPIO27
J1 P1 - D1 A
U1 GPIO23 - U2 A6
R5 P2 - J5 Pin_2
F1 2 - U3 VI
F1 2 - U3 VI
R3 P2 - J3 Pin_2
U5 RO - U1 GPIO26
U7 DefOpen - R12 P1
RV1 CW - VR1 CW
RV1 CW - VR1 CW
F1 2 - U3 VI
RV1 CW - VR1 CW
U9 DefOpen - R14 P1
RV1 CW - VR1 CW
VR1 WIPER - C12 P1
R36 P2 - C40 P1
VR7 WIPER - C18 P1
R23 P2 - U7 LED +
RV1 CW - VR1 CW
VR10 WIPER - C21 P1
RV1 CW - VR1 CW
U1 GPIO13 - R27 P1
VR2 WIPER - C13 P1
U1 GPIO13 - R27 P1
U1 GPIO18 - U2 A2
RV1 CW - VR1 CW
F1 2 - U3 VI
J11 Negative - J12 Negative
F1 2 - U3 VI
RV1 CW - VR1 CW
RV1 CW - VR1 CW
SW4 2 - R18 P1
VR4 WIPER - C15 P1
F1 2 - U3 VI
R3 P2 - J3 Pin_2
VR7 WIPER - C18 P1
VR5 WIPER - C16 P1
U6 AIN- - R34 P1
R9 P2 - J9 Pin_2
U2 B6 - R9 P1
J11 Positive - J12 Positive
RV1 CW - VR1 CW
SW1 DefOpen - R11 P1
U7 DefOpen - R12 P1
RV1 CW - VR1 CW
F1 2 - U3 VI
RV1 CW - VR1 CW
VR5 WIPER - C16 P1
SW6 2 - R19 P1
VR1 WIPER - C12 P1
SW2 2 - R16 P1
U3 + OUT - U4 VIN
J2 P1 - D2 A
RV1 CW - VR1 CW
U8 DefOpen - R13 P1
U2 B5 - R8 P1
SW3 2 - R17 P1
U10 DefOpen - R15 P1
R5 P2 - J5 Pin_2
R8 P2 - J8 Pin_2
U1 GPIO18 - U2 A2
U6 AOUT - R35 P2
U1 GPIO19 - U2 A3
R24 P2 - U8 LED +
J11 Negative - J12 Negative
VR10 WIPER - C21 P1
VR3 WIPER - C14 P1
U3 + OUT - U4 VIN
VR9 WIPER - C20 P1
R22 P2 - SW1 LED +
R32 P2 - R33 P1
R32 P2 - R33 P1
R4 P2 - J4 Pin_2
U1 GPIO21 - U2 A4
U7 DefOpen - R12 P1
J11 Positive - J12 Positive
SW1 DefOpen - R11 P1
RV1 CW - VR1 CW
U6 AOUT - R35 P2
R10 P2 - J10 Pin_2
F1 2 - U3 VI
R6 P2 - J6 Pin_2
U8 DefOpen - R13 P1
U2 B6 - R9 P1
F1 2 - U3 VI
RV1 CW - VR1 CW
R20 P1 - U1 EN
VR9 WIPER - C20 P1
J1 P1 - D1 A
F1 2 - U3 VI
VR2 WIPER - C13 P1
R6 P2 - J6 Pin_2
U1 GPIO16 - U2 A0
R23 P2 - U7 LED +
RV1 WIPER - C11 P1
GND
GND
RV1 WIPER - C11 P1
VR6 WIPER - C17 P1
VR3 WIPER - C14 P1
SW2 2 - R16 P1
RV1 CW - VR1 CW
U2 B3 - R6 P1
R26 P2 - U10 LED +
U3 + OUT - U4 VIN
SW6 2 - R19 P1
U2 B2 - R5 P1
U2 B0 - R3 P1
J11 Negative - J12 Negative
RV1 CW - VR1 CW
J11 Positive - J12 Positive
R9 P2 - J9 Pin_2
U8 DefOpen - R13 P1
U1 GPIO14 - R28 P1
RV1 CW - VR1 CW
U10 DefOpen - R15 P1
J11 Positive - J12 Positive
F1 2 - U3 VI
SW1 DefOpen - R11 P1
U3 + OUT - U4 VIN
U2 B4 - R7 P1
F1 2 - U3 VI
F1 2 - U3 VI
U1 GPIO14 - R28 P1
U3 + OUT - U4 VIN
J11 Positive - J12 Positive
F1 2 - U3 VI
U1 GPIO19 - U2 A3
U9 DefOpen - R14 P1
U3 + OUT - U4 VIN
R8 P2 - J8 Pin_2
VR7 WIPER - C18 P1
U1 GPIO25 - U2 A7
U6 AIN- - R34 P1
RV1 CW - VR1 CW
SW4 2 - R18 P1
D1 K - D2 K
U1 GPIO14 - R28 P1
R7 P2 - J7 Pin_2
RV1 CW - VR1 CW
RV1 CW - VR1 CW
U3 VO_Adj - R37 P1
SW2 2 - R16 P1
RV1 CW - VR1 CW
U2 B1 - R4 P1
U1 GPIO25 - U2 A7
R4 P2 - J4 Pin_2
D1 K - D2 K
R24 P2 - U8 LED +
SW6 2 - R19 P1
U1 GPIO17 - U2 A1
VR3 WIPER - C14 P1
VR8 WIPER - C19 P1
U5 DI - U1 GPIO27
R7 P2 - J7 Pin_2
U1 GPIO23 - U2 A6
U2 B4 - R7 P1
RV1 CW - VR1 CW
U2 B1 - R4 P1
RV1 CW - VR1 CW
U2 B7 - R10 P1
D1 K - D2 K
F1 2 - U3 VI
RV1 CW - VR1 CW
RV1 CW - VR1 CW
VR6 WIPER - C17 P1
SW4 2 - R18 P1
R25 P2 - U9 LED +
VR10 WIPER - C21 P1
RV1 WIPER - C11 P1
U3 + OUT - U4 VIN
U1 GPIO16 - U2 A0
R20 P1 - U1 EN
RV1 CW - VR1 CW
U5 ~RE~ - U1 GPIO32
VR2 WIPER - C13 P1
U1 GPIO13 - R27 P1
U6 AIN- - R34 P1
U3 VO_Adj - R37 P1
U1 GPIO21 - U2 A4
R10 P2 - J10 Pin_2
RV1 CW - VR1 CW
J2 P1 - D2 A
RV1 CW - VR1 CW
SW3 2 - R17 P1
U1 GPIO17 - U2 A1
SW3 2 - R17 P1
U2 B5 - R8 P1
U1 GPIO13 - R27 P1
RV1 CW - VR1 CW
RV1 CW - VR1 CW
RV1 CW - VR1 CW
D1 K - D2 K
U5 ~RE~ - U1 GPIO32
U9 DefOpen - R14 P1
U2 B7 - R10 P1
U2 B2 - R5 P1
D1 K - D2 K
VR4 WIPER - C15 P1
U1 GPIO22 - U2 A5
R26 P2 - U10 LED +
U10 DefOpen - R15 P1
F1 2 - U3 VI
F1 2 - U3 VI
VR9 WIPER - C20 P1
U6 AOUT - R35 P2
R25 P2 - U9 LED +
U2 B3 - R6 P1
RV1 CW - VR1 CW
RV1 CW - VR1 CW
U3 + OUT - U4 VIN
F1 2 - U3 VI
RV1 CW - VR1 CW
R36 P2 - C40 P1
VR1 WIPER - C12 P1
RV1 CW - VR1 CW
VR4 WIPER - C15 P1
RV1 CW - VR1 CW
RV1 CW - VR1 CW
RV1 CW - VR1 CW
J11 Negative - J12 Negative
VR5 WIPER - C16 P1
RV1 CW - VR1 CW
R36 P2 - C40 P1
U5 RO - U1 GPIO26
U3 + OUT - U4 VIN
R22 P2 - SW1 LED +
VR6 WIPER - C17 P1
RV1 CW - VR1 CW
U1 GPIO14 - R28 P1
VR8 WIPER - C19 P1
U1 GPIO22 - U2 A5
U2 B0 - R3 P1
R22
Resistance
1.5kΩ
U10 LED - - R11 P2
GND
MH1 terminal - U12 terminal
R7
Resistance
330Ω
GND
R9
Resistance
330Ω
GND
GND
U11 VSS - U11 A0
RV1 CCW - VR1 CCW
R31
Resistance
560Ω
R16 P2 - R17 P2
U10 LED - - R11 P2
R35
Resistance
100kΩ
GND
GND
RV1 CCW - VR1 CCW
R16 P2 - R17 P2
GND
R26
Resistance
1.5kΩ
RV1 CCW - VR1 CCW
GND
R34
Resistance
2kΩ
J3 Pin_3 - J4 Pin_3
GND
GND
GND
U10 LED - - R11 P2
GND
RV1 CCW - VR1 CCW
R12
Resistance
10kΩ
GND
R4
Resistance
330Ω
R37
Resistance
21kΩ
R31 P2 - J11 GND
GND
GND
RV1 CCW - VR1 CCW
R29
Resistance
120Ω
RV1 CCW - VR1 CCW
RV1 CCW - VR1 CCW
RV1 CCW - VR1 CCW
GND
R31 P2 - J11 GND
RV1 CCW - VR1 CCW
GND
R3
Resistance
330Ω
RSHUNT1
Resistance
0.0005 ohms
GND
GND
GND
R25
Resistance
1.5kΩ
R20
Resistance
10kΩ
U11 VSS - U11 A0
RV1 CCW - VR1 CCW
R16 P2 - R17 P2
RV1 CCW - VR1 CCW
R23
Resistance
1.5kΩ
RV1 CCW - VR1 CCW
J3 Pin_3 - J4 Pin_3
RV1 CCW - VR1 CCW
R16 P2 - R17 P2
RV1 CCW - VR1 CCW
GND
U10 LED - - R11 P2
GND
R18
Resistance
10kΩ
U10 LED - - R11 P2
GND
J3 Pin_3 - J4 Pin_3
RV1 CCW - VR1 CCW
U10 LED - - R11 P2
GND
R15
Resistance
10kΩ
J3 Pin_3 - J4 Pin_3
RV1 CCW - VR1 CCW
MH1 terminal - U12 terminal
J3 Pin_3 - J4 Pin_3
R13
Resistance
10kΩ
R30
Resistance
560Ω
GND
RV1 CCW - VR1 CCW
R28
Resistance
4.7kΩ
MH1 terminal - U12 terminal
RSHUNT1 P2 - R34 P2
RV1 CCW - VR1 CCW
R8
Resistance
330Ω
R36
Resistance
1kΩ
U6 BIN- - U6 BOUT
GND
GND
RV1 CCW - VR1 CCW
J3 Pin_3 - J4 Pin_3
R31 P2 - J11 GND
GND
J3 Pin_3 - J4 Pin_3
R11
Resistance
10kΩ
R19
Resistance
10kΩ
GND
GND
GND
GND
U6 BIN- - U6 BOUT
R24
Resistance
1.5kΩ
RSHUNT1 P2 - R34 P2
GND
GND
R32
Resistance
10 kΩ
R33
Resistance
3.3 kΩ
J3 Pin_3 - J4 Pin_3
RV1 CCW - VR1 CCW
GND
R10
Resistance
330Ω
GND
GND
R21
Resistance
10kΩ
MH1 terminal - U12 terminal
R6
Resistance
330Ω
RV1 CCW - VR1 CCW
R16
Resistance
10kΩ
R17
Resistance
10kΩ
R5
Resistance
330Ω
R14
Resistance
10kΩ
R27
Resistance
4.7kΩ
RV1 CCW - VR1 CCW
VR2
C24
Capacitance
100nF
C16
Capacitance
100nF
C28
Capacitance
100nF
C11
Capacitance
100nF
C14
Capacitance
100nF
C17
Capacitance
100nF
VR4
VR1
C12
Capacitance
100nF
C31
Capacitance
100nF
C20
Capacitance
100nF
C30
Capacitance
100nF
C22
Capacitance
100nF
C23
Capacitance
100nF
C19
Capacitance
100nF
C34
Capacitance
100nF
C33
Capacitance
100nF
C32
Capacitance
100nF
C37
Capacitance
10uF
C25
Capacitance
100nF
C39
Capacitance
10uF
C21
Capacitance
100nF
VR6
C29
Capacitance
100nF
C38
Capacitance
10uF
VR3
C40
Capacitance
100nF
C36
Capacitance
10uF
C26
Capacitance
100nF
VR9
C6
Capacitance
1000uF
C13
Capacitance
100nF
C15
Capacitance
100nF
VR8
VR10
C7
Capacitance
1000uF
C8
Capacitance
470uF
C35
Capacitance
100nF
RV1
C18
Capacitance
100nF
C10
Capacitance
470uF
VR5
C27
Capacitance
100nF
VR7
SW3
U6
U5
U11
U3
MH3
MH2
SW2
U2
D2
MH4
SW4
MH1
D1
SW6
J8
J4
J2
J11
J10
J6
J9
J1
J7
J12
J3
F1
J5
D3

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Platform & Toolchain
  • MCU: ESP32-DEVKITC-32UE
  • Framework: Arduino on PlatformIO
  • Build command: pio run
  • Flash command: pio run -t upload
  • Monitor command: pio device monitor
Pin Mapping

Table


FunctionGPIO / PinSchematic netNotes
I2C SDAGPIO23I2C_SDAOLED + MCP23017
I2C SCLGPIO25I2C_SCLOLED + MCP23017
DMX RXU1 RX / GPIO3DMX_RXUART receive from SP3485 RO
DMX TXU1 TX / GPIO1DMX_TXUART transmit to SP3485 DI
DMX DE/REGPIO26DMX_DE_REHIGH transmit, LOW receive
LED 1..8GPIO13,14,16,17,18,19,21,22ESP_LED1..8WS2815 data via 74HCT245 + 330R
PotsVP,VN,GPIO34,35,33,4,15,2,12,0,5POT1_ADC..POT11_ADCAnalog controls; review boot-strap use in firmware/prototype
Battery ADCGPIO32BATTERY_ADC100k/22k divider: 15V input ≈ 2.70V ADC
Current sense ADCGPIO33CURRENT_SENSE_ADCLM358 low-side shunt sense output
Buttons/togglesMCP23017 GPA0..4, GPB0..3BTN1..5, TOGGLE_*, LOW_BATT_OVERRIDEI2C expander inputs
platformio.ini

Ini


[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
monitor_speed = 115200
lib_deps =
  adafruit/Adafruit SSD1306@^2.5.10
  adafruit/Adafruit GFX Library@^1.11.9
  adafruit/Adafruit MCP23X17@^2.3.2
Complete Starter Source

Cpp


#include <Arduino.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_MCP23X17.h>

#define PIN_I2C_SDA 23
#define PIN_I2C_SCL 25
#define PIN_DMX_RX 3
#define PIN_DMX_TX 1
#define PIN_DMX_DE_RE 26

const uint8_t LED_PINS[8] = {13,14,16,17,18,19,21,22};
const uint8_t POT_PINS[11] = {36,39,34,35,33,4,15,2,12,0,5};
#define PIN_BATTERY_ADC 32
#define PIN_CURRENT_ADC 33

Adafruit_SSD1306 display(128, 64, &Wire, -1);
Adafruit_MCP23X17 mcp;
HardwareSerial DMXSerial(2);

void setDmxReceive() { digitalWrite(PIN_DMX_DE_RE, LOW); }
void setDmxTransmit() { digitalWrite(PIN_DMX_DE_RE, HIGH); }

void setupInputs() {
  for (uint8_t i = 0; i < 8; i++) pinMode(LED_PINS[i], OUTPUT);
  pinMode(PIN_DMX_DE_RE, OUTPUT);
  setDmxReceive();
  for (uint8_t pin = 0; pin <= 8; pin++) mcp.pinMode(pin, INPUT);
}

void setup() {
  Serial.begin(115200);
  Wire.begin(PIN_I2C_SDA, PIN_I2C_SCL);
  DMXSerial.begin(250000, SERIAL_8N2, PIN_DMX_RX, PIN_DMX_TX);
  mcp.begin_I2C(0x20, &Wire);
  setupInputs();
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,0);
  display.println("Carousel LED CTRL");
  display.display();
}

void loop() {
  uint16_t pots[11];
  for (uint8_t i = 0; i < 11; i++) pots[i] = analogRead(POT_PINS[i]);
  uint16_t batt = analogRead(PIN_BATTERY_ADC);
  uint16_t current = analogRead(PIN_CURRENT_ADC);
  uint16_t inputs = 0;
  for (uint8_t pin = 0; pin <= 8; pin++) if (mcp.digitalRead(pin)) inputs |= (1 << pin);

  display.clearDisplay();
  display.setCursor(0,0);
  display.printf("BattADC:%u\nCurrADC:%u\nInputs:%03X", batt, current, inputs);
  display.display();

  while (DMXSerial.available()) {
    uint8_t b = DMXSerial.read();
    (void)b;
  }
  delay(50);
}
Bring-up Notes
  • Keep DMX transceiver receive mode by default; only drive transmit if firmware intentionally sends DMX/RDM data.
  • GPIO1/GPIO3 are also USB-serial pins on many ESP32 DevKit boards; avoid logging while receiving/transmitting DMX or move DMX UART if the selected DevKit wiring requires it.
  • Several pot ADC nets use ESP32 strap-sensitive pins; verify boot behavior during prototype bring-up.
  • Calibrate BATTERY_ADC from measured input voltage. With R32=100k and R33=22k, Vin = Vadc * (122.0 / 22.0).
  • Calibrate CURRENT_SENSE_ADC from measured load current. The schematic targets low-side shunt sensing with an LM358 gain stage; final calibration depends on the installed shunt tolerance and gain-resistor tolerances.
  • Platform & Toolchain

  • Pin Mapping

  • `platformio.ini`

  • Complete Starter Source

  • Bring-up Notes

Carousel Horse LED Controller

Carousel Horse LED Controller thumbnail
Production-ready ESP32-DEVKITC-32UE festival carousel horse LED controller schematic with organized Power, ESP32 + Level Shifter + LEDs, Inputs, and DMX + OLED blocks.

Properties

Properties describe core aspects of the project.

Pricing & Availability

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Qty 1

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TME

$11.05

Verical

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Controls