Connecting ESP8266 to 10016BH display - how to read the status?

Question 1

No. A misconfigured ESP output can fight the display driver. "Therefore, give resistors." Insert series resistors or Schottky isolation when sensing. Prefer tapping the driver or its bus, not LED pins. [Elektroda, dasej, post #18645781]

Answer

No. A misconfigured ESP output can fight the display driver. "Therefore, give resistors." Insert series resistors or Schottky isolation when sensing. Prefer tapping the driver or its bus, not LED pins. [Elektroda, dasej, post #18645781]

Question 2

One measurement showed ~4.9 V before the resistor and ~1.9 V across a lit LED. The same point read 0 V when that segment was off. Use these levels to choose level shifting or diode logic for your inputs. [Elektroda, evolucja, post #18646196]

Answer

One measurement showed ~4.9 V before the resistor and ~1.9 V across a lit LED. The same point read 0 V when that segment was off. Use these levels to choose level shifting or diode logic for your inputs. [Elektroda, evolucja, post #18646196]

Question 3

Avoid GPIO0, GPIO2, and GPIO15 because they control boot and can toggle at reset. Prefer GPIO4, GPIO5, GPIO12, GPIO13, or GPIO14 for inputs. Configure them as INPUT or INPUT_PULLUP as needed. Edge case: some pins briefly drive at boot, risking collisions. [“ESP8266 Pinout Reference”]

Answer

Avoid GPIO0, GPIO2, and GPIO15 because they control boot and can toggle at reset. Prefer GPIO4, GPIO5, GPIO12, GPIO13, or GPIO14 for inputs. Configure them as INPUT or INPUT_PULLUP as needed. Edge case: some pins briefly drive at boot, risking collisions. [“ESP8266 Pinout Reference”]

Question 4

Enable pull‑ups on ESP inputs and add Schottky diodes from each 74HC595 output. Common‑anode segments are active‑low at the driver. The active output pulls the ESP input down through the diode, giving isolation and correct logic. [Elektroda, ArturAVS, post #18648150]

Answer

Enable pull‑ups on ESP inputs and add Schottky diodes from each 74HC595 output. Common‑anode segments are active‑low at the driver. The active output pulls the ESP input down through the diode, giving isolation and correct logic. [Elektroda, ArturAVS, post #18648150]

Question 5

Add series resistors on each sense line. They limit the "collision" current if an ESP pin drives accidentally. This protects both controllers during programming or resets. [Elektroda, ArturAVS, post #18648712]

Answer

Add series resistors on each sense line. They limit the "collision" current if an ESP pin drives accidentally. This protects both controllers during programming or resets. [Elektroda, ArturAVS, post #18648712]

Question 6

Yes. About 1.9 V is not a valid high for ESP8266. Use a MOSFET translator, such as a BSS138 level shifter. "Feeding 1V9 to the input ... will result in 3V3 at the output." Tie grounds together. [Elektroda, khoam, post #18646324]

Answer

Yes. About 1.9 V is not a valid high for ESP8266. Use a MOSFET translator, such as a BSS138 level shifter. "Feeding 1V9 to the input ... will result in 3V3 at the output." Tie grounds together. [Elektroda, khoam, post #18646324]

Question 7

Yes. Connect to SER, SRCLK, and RCLK to capture display data. Configure the ESP as an SPI‑slave sniffer to read what the MCU sends. This uses three lines and avoids LED‑level quirks. [Elektroda, tmf, post #18648704]

Answer

Yes. Connect to SER, SRCLK, and RCLK to capture display data. Configure the ESP as an SPI‑slave sniffer to read what the MCU sends. This uses three lines and avoids LED‑level quirks. [Elektroda, tmf, post #18648704]

Question 8

Yes. "The ESP and controller grounds must be connected." Shared ground ensures correct logic thresholds and stable readings. Without it, level shifters and inputs misbehave. [Elektroda, khoam, post #18646324]

Answer

Yes. "The ESP and controller grounds must be connected." Shared ground ensures correct logic thresholds and stable readings. Without it, level shifters and inputs misbehave. [Elektroda, khoam, post #18646324]

Question 9

Sample the seven segment lines and compare against a lookup table. Invert bits if your hardware is common‑anode. This quickly translates segment patterns into digits. [Elektroda, BlueDraco, post #18645717]

Answer

Sample the seven segment lines and compare against a lookup table. Invert bits if your hardware is common‑anode. This quickly translates segment patterns into digits. [Elektroda, BlueDraco, post #18645717]

Question 10

It’s an SMD code, not the value itself. "308 is a code designation not a value." Boards here used about 2 kΩ, but always measure to confirm. Do not rely on marking alone. [Elektroda, dasej, post #18645819]

Answer

It’s an SMD code, not the value itself. "308 is a code designation not a value." Boards here used about 2 kΩ, but always measure to confirm. Do not rely on marking alone. [Elektroda, dasej, post #18645819]

Question 11

Answer

Identify SER, SRCLK, and RCLK on the board and wire them to ESP inputs.
Set the ESP to SPI‑slave and sample on SRCLK; latch on RCLK edges.
Decode the shifted byte in firmware to segment states. [Elektroda, tmf, post #18648704]

Question 12

Yes. The 74HC595 sinks current to light a segment in this configuration. The driver output goes low for a lit segment. Design code and diode sensing for active‑low logic. [Elektroda, ArturAVS, post #18648150]

Answer

Yes. The 74HC595 sinks current to light a segment in this configuration. The driver output goes low for a lit segment. Design code and diode sensing for active‑low logic. [Elektroda, ArturAVS, post #18648150]

Connecting ESP8266 to 10016BH display - how to read the status?

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