Wiring schematic

The wire list and a port-by-port check are in the build guide. Open the SVG file.

Handheld game console wiring schematic Handheld game console: complete wiring schematic Waveshare ESP32-S3-Touch-LCD-4.3B: inside the board (simplified from Waveshare's schematic) USB-Cto PC for updates TF card slotnot used BOOTupdates RESETbutton LCD ribbonfactory fitted Touch ribbonfactory fitted RTC, CR927not used MX1.25 lithium headerNEVER connect AA pack SW1 battery switchleave OFF SW2 CAN, RS485 120 Ω switchleave off VBUS (USB 5 V) Q4 one-way switchDC_5V to VBUS DC_5V, about 5.2 V U1 SY8293 buckNo reverse protection Q3 from VBUS5 V rail U8 SGM22123.3 V, 800 mA H8 resistor: 3V3 fitted5 V is the other option U9 ESP32-S3-WROOM-1GPIO8 = SDA, GPIO9 = SCLUSB on GPIO19, GPIO20 SDA, SCL (3V3 side) M1 NDC7002Nlevel shifter4.7 kΩ pull-ups CAN, TJA1051not used RS485, SP3485not used Opto outputsnot used U11 CH422G I/O expander IO2: backlight enable, 4.7 kΩ pull-up to 5 V, so it stays on in input mode IO3: LCD reset, no pull-up on the schematic (check on the real board) IO0 and IO5: button inputs 5 V through D4 1N5822then R79 220 Ω 3.6 kΩ 3.6 kΩ T5 PC814opto T6 PC814opto EXIO04.7 k to 3V3 EXIO54.7 k to 3V3 12345678910111213141516 VINGNDVOUTGNDSDASCL GNDDI0DI1 LHBADO0DO1COM 7-36 VI2C_VCCD_SDAD_SCLCANLCANH485 TX-485 TX+DOUT0DOUT1DI_COMDIN0DIN1 RockerKCD11 SPST +- 6 x AA holder, 9 VRed +, black -, 6 in leads GNDVCCSDASCLGNDOUT MCP4725 DAC module, 6-pin header, 2.7-5.5 V Pads: ADDR jumper (GND or VCC, default expected GND = 0x60) I2C PULLUPS jumper on the back: leave as supplied. Row shown right to left. A+A-SDVinGnd PAM8302 amp, 2-5.5 V, up to 24 dB Vol trim on board: start it turned low +- open Speaker8 Ω, 1 W, 20 mmPre-wired, 4 in leads LeftRight 1234 1234 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Line colors (for reading the drawing, not required wire colors) Battery 9 V VOUT 3.3 V Ground SDA SCL Audio Speaker Button signal Numbered circles match the wire list. A hop means the wires do not touch. Terminals 3, 4 and 14 each hold two wires under one screw. Tactile pins 1-2 and 3-4 are joined inside. Wiring a tactile switch at diagonal pins 1 and 4 works whichever way it is rotated. Check battery polarity before first power. Turn the rocker OFF before plugging USB into a PC. Not yet tested on real hardware. Check pin labels against the parts in hand.