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 
		Applesoft program 
		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 
		values ) 
		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  
  and  27128,
		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 
		"stepupconverter" -
		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 
		are links  
		- to .PDF file ( German with entire content in high resolution ) 
		and  
		- link to diskimage with program ( DOS 3.3 - 5,25 Disk 140 kB ) ! 
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