Introduction

EPROM Programmers come in different sizes and are designed to program individual chips that either plug directly or use additional adapters before connecting to the ZIF zero-insertion sockets supplied with the programmer.

In some cases the physical chip is not always available. Sometimes the EPROM programmer could be able to program a chip if the In the case of some older 8-bit game computers and the Z88 card for example, the flash or EPROM chip is inside a plug-able module. The address and data lines are available via a bespoke connector. The EPROM programmer could also program a chip with more memory than the programmer is normally able to program if the most significant bit individual address signal lines are changed , so a larger size device could by hardware. Larger size devices could then be programmed in multiple steps. In the case of the Z88 where either a flash or EPROM chip could be programmed in a moduleFinally the user may know which signals need to be swapped, changed or held at a different logic level and would welcome a board to try different combinations before the solution is found, either be theory or by trail and error.

The object of this card is to design a PCB that can be used in a variety of ways depending which components are fitted allowing the user to have full hardware control of the signals used.

Types of EPROM Programmers

The following types of EPROM Programmers have been identified.

• 32 pin
• 40 pin
• 48 pin

The 40 and 48 pin programmers are able to program larger memory devices as they have more address lines available. Allowing the user to manually set these additional address lines allows the most significant bit individual address signal lines using tri-state switches, allow these larger devices to be programmed by a 32 pin programmer.

They also either have the The lever that either grips the chip can either be at the top left-hand side or the bottom right-hand side of the ZIF socket. The card needs to be designed so that it does not fowl the lever.

Design

The design of the card is split in 3 parts where the first and last parts are similar and the middle part translates the desired signals.

Input - Plug to fit into the ZIF socket of the EPROM programmer

• Address Tri-state switches
• Space for 2 off 24 pin headers to be used so that for 48 pin programmers. Shorter lengths may be usedfitted for the smaller sizes of programmers.
• These headers are repeated so that if jumper wires may be usedare used to connect directly to the output.
• Tracks are marked with a section that allows them to be permantly be permanently cut.
• Tracks Another row of headers may be fitted the other side of these cuts, so that the tracks may be reconnected using a header linklinks.

Translation Section

• 2 x 12 way DIP switches
• Address Tri-state switches (?)

Output - 48 pin ZIF Socket 

• This allows up to the a maximum size 48 pin zif socket to be used.
• The headers are repeated so that jumper wires may be used.
• Tracks are marked with a section that allows them to be permanently be cut.
• Tracks may be reconnected using a header link
• 48 pin IDC connector to allow connection to non standard external cards
• Z88 card socket connector

Space