NIStune Type 1 Hardware Installation Page 32 of 32
10. Reading the factory ROM image
ECU Type A (1984-1985)
These ECUs have two non-standard ROM chips (1K and 8K) which require special adaptors to read them in
a standard EPROM programmer. It is recommended you send the ECU to NIStune developments for
reading and board installation. We plan to make adaptors available in the future.
ECU Type B (1986)
These ECUs have a standard 27C128 (16K) compatible ROM and non-standard MB7132 (1K) ROM chip.
The second smaller chip requires a special adaptor for reading. It is recommended you send the ECU to
NIStune developments for reading. However we may already have the ROM image for most of these type of
ECUs here, so please check with us.
ECU Types C, D
These ECUs have a standard 27C128/27C256 EPROM chip. After removing the EPROM chip from your
ECU, you may need to read these using an EPROM programmer. You need to either read them as a 27C128
or a 27C256 chip.
Programmer Information
There are many different types of EPROM programmers available. One of the common programmers is the
Willem as pictured below.
The software for your programmer will allow you to select the chip type you wish to read and load it into
memory, and then save it as a file afterwards. Note: For the Willem programmer, ensure you have the
switch settings as specified in the software