IEC2IEEE

                          Without any warranty - own risk

is an interface which translates from the serial IEC-bus of the C64 to the
parallel IEEE-bus of older Commodore-drives like f.e. the SFD-1001. It
supports fast JiffyDOS IEC-bus routines. It's very easy to build oneself and
it's very cheap, about 15.- $/Euros.
First you must build the cuircuit. See the cuircuit-text and the picture at
the homepage www.nlq.de.
You can see the necessary parts f.e. at www.reichelt.de: 

Amount Reichelt-order-number Price
 1     H25 PR075             0,87         circuit-board
 1     ATMega8515-16DIP      4,25         Atmel microcontroller
 1     GS40                  0,11         socket
 1     ZL 214SWW-5           0,77         electric 5V cable
 1     D-SUB BU09            0,10         C64-joystick-plug (for 5V)
 1     KAPPE CG9G            0,09         housing for plug
 1     rad 22/16             0,04         capacity
 1     STIFTL.36G            0,17         pins
 1     LED 3mm 2MA rt        0,09         LED 
10     1/4W 1,8k             0,033        resistors 
 1     AVK 150               0,82         serial cable (cut in two parts)
 1     AWG 28-16G 3m         2,15         parallel cable (cut)
 1     SE 5724 N             1,45         IEEE-plug
 3    (old) Jumpers           -
      (housing)               ?
----------------------------------
      Total (Euros):        11,24

The input-amplifier-chip (74LS244) is only necessary if you want to use the
 serial bus even if the AVR is switched off.
The output-amplifier-chip (7407) is only necessayr if you use more than five
 different serial devices at the IEC-bus. You don't need them usually.

You should make jumper 'r' to position low/closed before connecting the
 circuit to the C64 when you program the AVR the first time. Then you can
 flash the AVR from the C64 over the serial bus using the C64-programm
 'c/avr-flasher'. The flashfile 'ledblnk-mega.obj' is a simple test for the
 LED only. 'iec2ieee.obj' is the flashfile for the adapter.

Next is to calibrate the AVR-internal oscylator to 7.37 MHz and to config
 the AVR-EEPROM which contains the values for the drive emulation. Use the
 program 'c/i2i-cal&con'.

'c/i2mem-reader' is for printing or reading values to find bugs. Please send
 an email to NLQ@gmx.de if there are bugs.

The 'c/' means that it's a compiled Basic-program (Austrospeed).

  This program is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2, or (at your option)
  any later version.

  Use of this software in other projects is allowed and encouraged; however,
  the author would like to be notified of any such projects.

   Jochen Adler   Near Letter Quantity  
   Haeldestr.9  D74912 Kirchardt  Germany
   NLQ@gmx.de  www.nlq.de

                      Without any warranty - own risk