SIMPLE-6809

Features

• Build of Grant Searles's Simple 6809 CPU
  • Runs BASIC
• 6809 CPU
• 1.8543 MHz
• 32KB SRAM
• 16KB 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

• 0x0000-0x7FFF 32KB SRAM
• 0x8000-0x9FFF Free Space (8KB)
• 0xA000-0xBFFF Serial (ACIA)
• 0xC000-0xCFFF 16KB EPROM

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-6809 Rev 1 Assembly Sheet