SIMPLE-Z80

Features

• Build of Grant Searles's Simple Z80 CPU
  • Runs BASIC
• Z80 CPU
• 7.3728 MHz clock
• 56KB SRAM (uses 128KB parts)
• 8KB EPROM/EEPROM
• 68B50 Serial Port (ACIA)
  • RS-232 port
  • Header for FTDI
  • 115,200 baud
• Reset switch with optional Power Supervisor
• 95x95mm card
• (4) 6-32 mounting holes

Memory Map

• 0x0000-0x1FFF 8KB ROM
• 0x2000-0xFFFF 56KB SRAM
• I/O
  • 0x00-0x7F - Free
  • 0x80-0x81 - Serial port (ACIA)

Headers

EPROM/EEPROM Select Jumpers

PART	J2 PIN 1	J5 PIN 27
27128 EPROM	VPP (5V)	PGM (5V)
27C256 EPROM	VPP (5V)	A14 (GND)
27C512 EPROM	A15 (GND)	A14 (GND)
SST27SF256 EEPROM	VPP (5V)	A14 (GND)
SST27SF512 EEPROM	A15 (GND)	A14 (GND)

Connectors

J1 - RS-232 Serial

1. N/C
2. Receive
3. Transmit
4. Loop to pin 6
5. GND
6. Loop to pin 4
7. RTS
8. N/C
9. N/C

J3 - FTDI / TTL Serial

1. GND
2. RTS* (out)
3. +5V
4. Receive (in)
5. Transmit (out)
6. N/C

J4 - 5V Power

• 2x4 header

Mechanicals

Assembly Sheet

SIMPLE-Z80 Rev 1 Assembly Sheet