This is also a rather unusual project using the Gameport as controlling
port for a eprom progamming device.
even though i have not translated the published description at the
moment - this Unit might be interesting
to every user of an Apple II
or II+ or //e. I have marked the lines in the source code of the
and placed translated text so that a user may be able to equip the menus
with translated english text and
then this programmer will be usable to the english speaking user.
I built this programmer back in 1981. This project page contains:
A) German description ( this will be
translated in next year - 2015 )
B) the circuitplan
C) the component layout and placement plan ( including the component
D) the pintables and their programming codes
E) the entire Applesoft source programm code
F) the entire Machinecode ( as example from the 2716 with marked area
which parts are different at other eproms )
G) the top-layer of the PCB
H) the solderside-layer of the PCB
I) a view of both layers combined together
J) the compunent layerplan of the PCB
K) a diskimage in .DSK format ( DOS 3.3 ) with Applesoftprogramm and
Machineprograms for different kinds of eproms
( related eprommachinecode parameterfiles ) and
several epromfiles ( compatible with ADT-transfer )
This eprom programmer has several features very
different from the usually used ones:
- Using the Gameport it is slotindependent because
it does not occupy any slot !
- It can program most common old epromtypes from
2508, 2516, 2716, 2532,
2732, 2732A, 2564, 2764
as long as the eprom uses either 21 Volt or 25
Volt programming voltage.
- due to the ability to trim the programming voltage you may also be
able to mofify for 12,5 Volt programming voltage
- green LED indicates Power on
- red LED indicates programming actiivity
- device has ability to check out if eprom is erased correct
- device can read eproms and save content to DOS 3.3 file
- display eprom content or epromfile at Monitor
- ability to manipulate epromfiles in RAM
The basic function works by
transfering data from gameport in serial manner to device and vice versa
the programming voltages 21Volt or 25 Volt are generated from the + 5
Volt of the gameport
( using internal voltage conversion at the device with NE555 as
no exotic ICīs used - the board only
contains standard logic ICs and standard transistors !
- therfore it is easy to build,
easy to use and easy
to mentain / repair !
At the bottom of page
- to .PDF file ( German with entire content in high resolution )
- link to diskimage with program ( DOS 3.3 - 5,25 Disk 140 kB ) !