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#Extending the design to new chip families # Extending the design to new chip families
##Hardware ## Hardware
There are currently two hardware flavors - one for 28C series EEPROMs and one specifically for the Intel 8255A UV EPROM. The 8755A chip uses a multiplexed set of address and data lines that are directly driven by the Arduino. Most other chips will not use this addressing method. The 8755A design aslso includes a circuit to switch the programming voltage under software control. This may be useful for other chips that use non-5V programming voltages, although many of these chips, like the 27 series EPROMS, have a programming voltage that remains for the entire write and verify cycle. For those chips, it may be easier to simply switch the programming voltage manually. There are currently two hardware flavors - one for 28C series EEPROMs and one specifically for the Intel 8255A UV EPROM. The 8755A chip uses a multiplexed set of address and data lines that are directly driven by the Arduino. Most other chips will not use this addressing method. The 8755A design aslso includes a circuit to switch the programming voltage under software control. This may be useful for other chips that use non-5V programming voltages, although many of these chips, like the 27 series EPROMS, have a programming voltage that remains for the entire write and verify cycle. For those chips, it may be easier to simply switch the programming voltage manually.
The basic hardware design, used for the 28C family. is much more adaptable to additional chip families. This design uses two shift registers to create 16 dedicated address lines from only 3 arduino pins. This design, plus manual switching of the program voltage, would be very adaptable to EPROMs like the 2716, 2764, 27040, and 272001. The hardware has already been used with these chips for read-only operations. The basic hardware design, used for the 28C family. is much more adaptable to additional chip families. This design uses two shift registers to create 16 dedicated address lines from only 3 arduino pins. This design, plus manual switching of the program voltage, would be very adaptable to EPROMs like the 2716, 2764, 27040, and 272001. The hardware has already been used with these chips for read-only operations.
#Software # Software
The software design is modular, allowing easy extenstion for chips with different programming algoritms. A new class can be added for each new chip family. This class will include code for byte reads, byte writes, and optional block writes, if the chip supports it. All of the chip-specific code will be in this single class. The software design is modular, allowing easy extenstion for chips with different programming algoritms. A new class can be added for each new chip family. This class will include code for byte reads, byte writes, and optional block writes, if the chip supports it. All of the chip-specific code will be in this single class.
The basic steps to support a new chip are as follows: The basic steps to support a new chip are as follows: