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Overview

Zeal 8-bit Computer is presented as a motherboard of size 15x10cm (5.91x3.94 in), containing integrated circuits in both Dual-Inline Package, or DIP, and Plastic Leaded Chip Carrier, or PLCC, format, with sockets. This makes them easy to pull in and out of the computer.

The computer also contains three connectors, the User Port, Extension port and Video Card connector, that are used to connect external boards or components to bring more features or capabilities to the system. These ports are all using the standard and well-known 2.54mm female sockets.

Some 2.54mm jumpers are also present on the motherboard. They let the user choose between configurations, they shall be properly set before powering it on. More about them later.

The following picture names the components and parts that are present on the board:

Zeal 8-bit Computer motherboard
  1. Zilog Z80 CPU
  2. Zilog Z80 PIO
  3. Two register files for the Memory Management Unit
  4. Octal buffer for the Memory Management Unit
  5. Programmable Logic Device acting as the Logic Glue
  6. 256KB NOR Flash acting as the ROM
  7. 512KB RAM
  8. Two 8-bit shifters used to decode the PS/2 Keyboard protocol
  9. Connector for the PS/2 Keyboard
  10. 10MHz active oscillator, main clock of the system
  11. 50-pin extension port
  12. 16-pin user port
  13. 40-pin video card connector
  14. I²C EEPROM
  15. I²C RTC
  16. Internal I²C connector
  17. Open-drain octal buffer used for I²C and blank video signals
  18. Reset switch
  19. Reset supervisory circuit
  20. 1A fuse
  21. Power switch
  22. USB-C power supply
  23. Power LED
  24. Battery for the I²C RTC

📝 Note

Components name marked on the Printed Board Circuit, or PCB, are here for reference, they may not always match the actual component that is plugged in. Before replacing or plugging any component, please refer to its datasheet and check whether it is compatible with the original one.