samedi 8 mars 2014

mercredi 5 mars 2014

C64 IEC interface schematics for DE0 nano, DE1 or DE2 board

IEC interface components :
  • 1 TTL 74LS06  six open collector buffer inverter
  • 6 resistors 2 kOhms  
Gpio side : 
  • connect to gpio_0 for DE0 Nano
  • connect to gpio_1 for DE1 or DE2
IEC side :
  • to IEC/SD board
  • to 1541 drive din connectors (+5V not connected )

FPGA64 for DE0 Nano, DE1, DE2-35

Keyboard main keys :
  • F11 toggle joystick emulation port A or port B on numeric keypad.
  • F12 toggle PAL / NTSC (some VGA monitor doesn't synched at 50Hz )
DE0 Nano switch :
  • key0 reset cpu
  • gpio_1_in0 toggle PAL / NTSC mode at startup (use F12 after startup)
  • gpio_1_in1 toggle15KHz (RBG SCART) / 31KHz (VGA)
DE1 switch :
  • key0 reset cpu
  • sw6 toggle PAL / NTSC mode at startup (use F12 after startup)
  • sw9 toggle 15KHz (RBG SCART) / 31KHz (VGA)  
DE2 switches :
  • key0 reset cpu
  • sw1 toggle PAL / NTSC mode at startup (use F12 after startup)
  • sw0 toggle 15KHz (RBG SCART) / 31KHz (VGA)  
 JiffyDos shortcut :
  • /FB load file browser from IEC drive
  • run 
  • @cd< goes out of D64 (< is the left arrow symbol not the 'less than' symbol)
  • @cd/ goes up one dir level
  • @cd// goes to root dir

New PCB for DE0 nano : low cost Multi I/O

On the PCB
  • Video DAC : RGB 3x4 bits, Hsync, Vsync ready for VGA 31KHz or RGB SCART 15KHz, 50/60Hz.
  • Audio DAC :   PWM stereo.
  • PS2 protocol (on PS2 plug or USB plug )
  • micro SD card socket
  • 2 inputs and 10 input/output with protection diodes (5v tolerant)
2 spare PCBs available
  • 20€ pcb alone (no components)
  • 35€ with surface mount components and sd socket (no connectors)

 Connected  to DE0 with straight ribbon cable