This is another project building a single board computer with an Z80 MCU alongside some RAM and ROM. In contrast to other well known projects I want to utilise an EEPROM which is very easy to handle. I also want to build a computer that works autonomously including an user interface and does not need additional microcontroller or a PC since both would be more powerful than the actual processor.

It is inspired by the SBC project by Grant Searle and therefore runs his modified version of Microsoft BASIC for the NASCOM computer. I further modified it for this SBC.

Before I explain the details, here is the result.

Overview

Z80 SBC overview

The specs are:

• MCU: Z80 in CMOS (Z84C006) at 7.3728 MHz
• RAM: 628128 SRAM
• ROM: AT28C256 EEPROM
• Display: 320×240 TFT with ILI9325 controller
• Keyboard with 64 keys
• Power consumption: 190 mA at 5V
• OS: NASCOM BASIC 4.7b

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