ECU Tuning Series – EPROM Programmers – Chip Tuning

Chip Tuning

Chip tuning is the oldest form of engine computer modification. Most early engine controllers used dedicated ROM memory chips. In order to change a chip’s operation, you had to physically remove the chip, reprogram it outside the ECU, and then reinstall it—a process called chipping. Users who expect

to make repeated modifications on older vehicles often install sockets in place of the ROM to allow easier insertion and removal of chips.

Automotive computers use many different kinds of memory chips. Some can be programmed only one time, but most can be erased and reused. Some older chips have a window on them and require UV-C light—a sterilizer—in order to erase them.

EPROM Programmers

Chip tuning generally requires an EPROM programmer, a device that reads, writes, and—if supported—programs chips. When chip tuning, be very careful to make sure that the programmer you buy works with the type of chip you intend to modify. There’s no such thing as a truly universal chip programmer. Here are a couple of popular EPROM programmers:

BURN2 A relatively cheap basic programmer (about $100) that supports common EPROMs used in chip programming. It features a USB interface with an open command set, along with many tuning   applications that already have native support.

WiIIem Another popular ROM burner (from $150 to $200, depending on the model). The original WiIIem used a parallel port interface, but newer versions is using USB.

Almost all EPROM programmers support only dual in-line package (DIP) chips. If your vehicle’s computer uses surface mount–style chips, you’ll probably need to purchase an appropriate additional adapter. It’s

generally a good idea to get any adapters from the same source as the programmer to ensure compatibility. All adapters should be considered custom hardware.This picture shows a ROM adapter board installed in a Mitsubishi ECU. The two empty 28-pin sockets in the lower-left corner have been added to the

original ECU. Some soldering is often required to modify and add ROM boards such as this one.

Chip Tuning

Chip tuning is the oldest form of engine computer modification. Most early engine controllers used dedicated ROM memory chips. In order to change a chip’s operation, you had to physically remove the chip, reprogram it outside the ECU, and then reinstall it—a process called chipping. Users who expect

to make repeated modifications on older vehicles often install sockets in place of the ROM to allow easier insertion and removal of chips.

Automotive computers use many different kinds of memory chips. Some can be programmed only one time, but most can be erased and reused. Some older chips have a window on them and require UV-C light—a sterilizer—in order to erase them.

EPROM Programmers

Chip tuning generally requires an EPROM programmer, a device that reads, writes, and—if supported—programs chips. When chip tuning, be very careful to make sure that the programmer you buy works with the type of chip you intend to modify. There’s no such thing as a truly universal chip programmer. Here are a couple of popular EPROM programmers:

BURN2 A relatively cheap basic programmer (about $100) that supports common EPROMs used in chip programming. It features a USB interface with an open command set, along with many tuning   applications that already have native support.

WiIIem Another popular ROM burner (from $150 to $200, depending on the model). The original WiIIem used a parallel port interface, but newer versions is using USB.

Almost all EPROM programmers support only dual in-line package (DIP) chips. If your vehicle’s computer uses surface mount–style chips, you’ll probably need to purchase an appropriate additional adapter. It’s generally a good idea to get any adapters from the same source as the programmer to ensure compatibility. All adapters should be considered custom hardware.This picture shows a ROM adapter board installed in a Mitsubishi ECU. The two empty 28-pin sockets in the lower-left corner have been added to the

original ECU. Some soldering is often required to modify and add ROM boards such as this one.