# ESP32 7-Segment Counter
## Description
ESP32-based 4-digit 7-segment counter using a 74HC595 shift register and three pushbuttons for increment, decrement, and reset.
## Project Details
- **Owner:** bjoern2004
- **Created:** 7/2/2026
- **Last Updated:** 7/3/2026
- **Visibility:** Public
## Key Components
### DS1 — [5461AS](https://www.flux.ai/jecstronic/5461as~pbk.md)
- Role Details: Common-cathode 4-digit 7-segment display multiplexed by ESP32 GPIO13/12/14/27
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Display
- Part Type: LED-Display
- Manufacturer Name: XLITX Technology
- Manufacturer Part Number: 5461AS
- Datasheet URL: http://www.xlitx.com/datasheet/5461AS.pdf
**Pins:**
- A [pin 11]
- B [pin 7]
- C [pin 4]
- D [pin 2]
- DP [pin 3]
- E [pin 1]
- F [pin 10]
- G [pin 5]
- GND 1 [pin 12]
- GND 2 [pin 9]
- GND 3 [pin 8]
- GND 4 [pin 6]
### J1 — [DB127V-5.08-2P-GN-S](https://www.flux.ai/cherepanyadima/db127v-5p08-2p-gn-s~ic.md)
- Role: Power Input
- Connector Positions: 2
- Part Type: Connector
- Connector Type: Screw Terminal
- Manufacturer Part Number: DB127V-5.08-2P-GN-S
- Datasheet URL: https://www.lcsc.com/datasheet/C3018698.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=ElhbUlFSRlUNBF0CQlQIBQBUFFILBFEAQVVWUgZWE1gxVlNRQVVdVFRSQ1daVDsOAxUeFF5JWBYZEEoBGA4JCwFIFA4DSA%3D%3D
- Manufacturer Name: DORABO
- Role Details: 2-pin 5.08 mm through-hole screw terminal: pin 1 VIN, pin 2 GND. Use regulated 5 V input for ESP32 DevKit VIN.
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### SW1 — [SWITCH-PUSH-6mm-H5mm-4pin](https://www.flux.ai/baronunread/switch-push-6mm-h5mm-4pin~4u.md)
- Part Type: Switch
- License: https://creativecommons.org/licenses/by/4.0/
- Role: User Input
- Role Details: +1 button to GPIO32, active low using ESP32 internal pull-up
**Pins:**
- 1-1 [pin 1-1]
- 1-2 [pin 1-2]
- 2-1 [pin 2-1]
- 2-2 [pin 2-2]
### SW2 — [SWITCH-PUSH-6mm-H5mm-4pin](https://www.flux.ai/baronunread/switch-push-6mm-h5mm-4pin~4u.md)
- Role: User Input
- Role Details: -1 button to GPIO33, active low using ESP32 internal pull-up
- License: https://creativecommons.org/licenses/by/4.0/
- Part Type: Switch
**Pins:**
- 1-1 [pin 1-1]
- 1-2 [pin 1-2]
- 2-1 [pin 2-1]
- 2-2 [pin 2-2]
### SW3 — [SWITCH-PUSH-6mm-H5mm-4pin](https://www.flux.ai/baronunread/switch-push-6mm-h5mm-4pin~4u.md)
- Role: User Input
- Role Details: Reset counter button to GPIO25, active low using ESP32 internal pull-up
- Part Type: Switch
- License: https://creativecommons.org/licenses/by/4.0/
**Pins:**
- 1-1 [pin 1-1]
- 1-2 [pin 1-2]
- 2-1 [pin 2-1]
- 2-2 [pin 2-2]
### U1 — ESP32 DevKit V1 30-pin GPIO13 Variant
- Role: Logic
- Datasheet URL: https://www.espboards.dev/esp32/esp32-30pin-devkit-generic/
- Package or Case Code: Module
- Manufacturer Part Number: ESP32 DevKit V1 30-pin GPIO13 Variant
- Manufacturer Name: Generic ESP32 DevKit
- Role Details: 30-pin ESP32 DevKit V1 variant created from public pinout to match GPIOs in sketch_v3.ino
- Part Type: Integrated Circuits
**Pins:**
- 3V3 [pin 15]
- EN [pin 1]
- GND [pin 16]
- GND [pin 22]
- GND [pin 13]
- GPIO12 [pin 12]
- GPIO13 [pin 30]
- GPIO14 [pin 11]
- GPIO16 [pin 27]
- GPIO17 [pin 26]
- GPIO18 [pin 24]
- GPIO19 [pin 23]
- GPIO2 [pin 29]
- GPIO21 [pin 21]
- GPIO22 [pin 18]
- GPIO23 [pin 17]
- GPIO25 [pin 8]
- GPIO26 [pin 9]
- GPIO27 [pin 10]
- GPIO32 [pin 6]
- GPIO33 [pin 7]
- GPIO34 [pin 4]
- GPIO35 [pin 5]
- GPIO36 [pin 2]
- GPIO39 [pin 3]
- GPIO4 [pin 28]
- GPIO5 [pin 25]
- RXD0 [pin 20]
- TXD0 [pin 19]
- VIN [pin 14]
### U2 — [CD74HC595M96](https://www.flux.ai/jecstronic/cd74hc595m96~uyk.md)
- Datasheet URL: https://www.ti.com/lit/ds/symlink/cd74hc595.pdf
- Part Type: Integrated Circuit
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Part Number: CD74HC595M96
- Role: Shift Register
- Role Details: ESP32 GPIO23/18/5 drive DS/SHCP/STCP; Q0-Q7 drive A-G/DP through resistors
- Manufacturer Name: Texas Instruments
**Pins:**
- GND [pin 8]
- OE [pin 13]
- QA [pin 15]
- QB [pin 1]
- QC [pin 2]
- QD [pin 3]
- QE [pin 4]
- QF [pin 5]
- QG [pin 6]
- QH [pin 7]
- QH¶ [pin 9]
- RCLK [pin 12]
- SER [pin 14]
- SRCLK [pin 11]
- SRCLR [pin 10]
- VCC [pin 16]
*The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/bjoern2004/esp32-7-segment-counter~i7](https://www.flux.ai/bjoern2004/esp32-7-segment-counter~i7).*
---
*Generated from [https://www.flux.ai/bjoern2004/esp32-7-segment-counter~i7](https://www.flux.ai/bjoern2004/esp32-7-segment-counter~i7)*