Circuit Diagrams
From SpecNext official Wiki
Contents
- 1 Schematic
- 2 J13 - Daughter board connector
- 3 J15 - Next GPIO
- 4 CN5 - Expansion bus (edge connector)
- 5 J10/J11 - Memory Expansion Ports
- 6 J4/J7 J8/J14 - Joystick Ports
- 7 CN1 - VGA Video Port
- 8 CN8 - Digital Port
- 9 CN2/CN6/CN7 - SD Reader (Mainboard) (CN6 on reverse)
- 10 CN10/CN11/CN12 - SD Reader (Daughterboard) (CN12 on reverse)
- 11 Accelerator Board
- 12 Real Time Clock (RTC)
- 13 CN9 - ESP8266-01/RS-232 Port
Schematic
The Issue 2B (rev 1) schematic can be downloaded here.
The thee tail matrix keyboard schematic can be downloaded here.
J13 - Daughter board connector
J15 - Next GPIO
CN5 - Expansion bus (edge connector)
J10/J11 - Memory Expansion Ports
J4/J7 J8/J14 - Joystick Ports
CN1 - VGA Video Port
Notes:
- In VGA mode (scandoubler enabled), H-SYNC and V-SYNC are carried separately on their respective pins.
- In RGB mode (scandoubler disabled), H-SYNC carries composite sync, and V-SYNC carries 1.
- Pin 14 carries 3V3, which can be connected to SCART pin 16 to indicate RGB to the display.
- There is no convenient source of voltages between 9.5-12V to indicate 4:3 aspect ratio to the display on SCART pin 8, so this is usually left unconnected.
CN8 - Digital Port
CN2/CN6/CN7 - SD Reader (Mainboard) (CN6 on reverse)
CN10/CN11/CN12 - SD Reader (Daughterboard) (CN12 on reverse)
Accelerator Board
Real Time Clock (RTC)
CN9 - ESP8266-01/RS-232 Port