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Fuel Injector Offsets Database
A comprehensive database of battery offset (dead time/latency) tables for OEM and aftermarket fuel injectors.
Wideband Installation Guide for Honda OBD1 ECUs
Learn how to install and configure an AEM wideband O2 sensor on your Honda OBD1 ECU using Honda Tuning Suite (HTS) or Ho...
`27C256` EPROM Specifications
Technical specifications, pinout diagrams, equivalent part numbers, and speed requirements for the 27C256 EPROM chip use...
`27SF256`
This is supposed to be an electricallyerasable replacement for 27 C256. SST Datasheet (PDF) These can be purchased dirt...
`28C256` EEPROM Pinout & Compatibility
Technical specifications, pinout mapping, and socket modification instructions for using the 28C256 EEPROM chip in stand...
`29C256`
the ATMEL AT29C256 chip is the de facto FLASHROM chip in use. It uses a 5V programming voltage, can be erased repeatedly...
`66207`
The Oki 66207 MCU is used mainly in the OBD1 Civic Integra ECUs. It uses the NX8/200 core. Lots of useful documentation...
`74HC373`
The 74HC373 is an octal Latch chip. It Latches 8 bits of data, and is usally used when adding an external rom to a MCU
`C144`
C144 is a NPN switching transistor. It has been successfully replaced with C2785 (and its replacements).
`MAX233`
the Maxim MAX233 chip is commonly used to translate between TTL and RS232 levels during serial communication.
02D011F0-1500
to convert nonvtec "11F0" boards from nonvtec to VTEC, add: In top left quadrant: C60 1uF, 35v electrolytic (tantalum?)...
02D01720-1500
To convert a "1720" board from nonvtec to VTEC add the following parts: Required: Q26: C2785 (note: I used a C144 and it...
02D01980-1500
Editor's note: the small list does not appear to have the required parts for the IABsAuthor: eg6ajk Date: 052403 15:10 m...
203 AC
Author: PRCIVIC Date: 052803 21:46 Ok I have commented the AC routine posted for the benefits of those with no assembly...
5050s
Use this method if you install a 5050s in IC14 and you get a MIL code 21. STEP 1 modify and install the VTEC parts as no...
5128XRAM
5128 XRAM explanation : The 5128 chip present in OBD0 ECUs is a 2K byte(?) SRAM chip. It is mapped into memory space at...
515X High Side Switch
Honda uses a 5 pin high side switch in a lot of their OBD1 and OBD2 ECUs to control solenoids like auto trans and VTEC s...
66k Assembler Docs
Here you can find all the documentation on the Oki 66K achitecture that we have been able to find. If it isn't attached...
66k Resources
Documentation 66k Assembler Docs factory documentation on the Oki 66xxx processors used in most OBD1 and OBD2 implemenat...
82C55 Programmable Peripheral Interface
Technical specifications and pinout mapping for the OKI MSM82C55A / Intel 82C55 Programmable Peripheral Interface (PPI)...
91PM6 Target Idle
Author: xtensive Date: 010403 20:47 Ok, here's what I found: That whole area is data tables. The routine that calls the...
A143
Thanks again Javier (dohcvtec): A143====Panasonic NTE2362 === (Digikey 2SB1030ARACTND) (do not be fooled into believing...
A5
A5h (opcode 'A5' in hexidecimal) is the "reserved" opcode of the 8051 instruction set. This means it is NOT a valid inst...
Acura Integra PR4 OBD0 ECU Pinouts and Wiring
Wiring layout, pinout details, and schematic analysis for the OBD0 and OBD1 Acura Integra PR4 ECU.
ADC
Analog to Digital Converter: An integrated circuit (IC) which converts an analog signal to a digital representation.
Add A Knock Sensor
Adding a knock sensor to an engine that did not come with one.
Add Knock To P30G00
On 1720 or 11f0 I've: remove R140, R141 10k add R107, R115, R116 220R I also add (they may not be essential): C94 4u7 16...
Adding IAB Control to an OBD1 P28 ECU
Hardware modification guide to add Intake Air Bypass (IAB) secondary runner controls to an OBD1 Honda P28 Civic ECU.
Adjust PR4 Pa Sensor
Dave Blundell sez "Vernon (deluded) sent me much of this info." As a rule of thumb, 90 PR4s have external PA sensors, an...
ASM662
ASM662 is an Oki 66201/66207/66301 assembler/disassembler which is still a work in progress. It's released under the BSD...
Auto To Manual
Most automatic ECUs can be converted to a 5spd rather easily. Going the other way often involves adding more components.
Automatic Accord OBD2-to-OBD1 ECU and TCU conversion
Wiring conversion guide and pinout translation tables to run an automatic OBD2a Accord using an automatic OBD1 Integra E...
Batronix USB Programmer
The Batronix USB Programmer is a slightly more polished product than their Eprommer3.3. As of October 9, 2003, it costs...
Beginner's Honda ECU FAQ
Archived beginner answers for identifying, selecting, and researching Honda ECUs.
C2785
C2785 is a high speed NPN switching transistor Thanks to Javier (dohcvtec) for a handy C2785 replacement.
CEL
Check Engine Light This indicator (usually on the dash) comes on to indicate that the ECU thinks something is wrong.
Checking Error Codes
https://web.archive.org/web/http://forum.pgmfi.org/viewtopic.php?t=4886See also Honda Error Codes
Chipping 1988-1989 OBD0 ECUs
Archived socketing and chipping methods for early 1988-1989 Honda and Acura OBD0 ECUs.
Chipping OBD1 Small Case
For a write up go to Chipping JDMP30
Chipping OBD2 Honda ECUs (OKI `66507` / `66P507`)
Hardware guide for chipping OBD2 Honda ECUs by replacing the OKI 66507 processor with a programmed 66P507 OTP microcontr...
Chipping the JDM OBD1 P30 ECU
Hardware modification guide for socketing, chipping, and converting JDM square-case OBD1 P30 ECUs to manual transmission...
Chipping the OBD0 PM6 ECU (1988–1991 Civic/CRX Si)
Step-by-step hardware guide to chipping the OBD0 PM6 ECU (1988–1991 Civic/CRX Si) to accept external EPROMs and custom t...
Chipping With Pictures
Chipping OBD0 PM6 Pictures of what needs to be done to chip a 9091 PM6/PM7/PR5/PR4/PP5/etc. Chipping OBD1 Big Case Pictu...
Converting the OBD1 P14 ECU to P13 (H23A to H22A)
Step-by-step component conversion guide to hardware-modify a non-VTEC OBD1 P14 ECU to function identically to a VTEC P13...
Crome ROM Tuning FAQ
Frequently asked questions about Crome, a popular ROM editing and tuning software for OBD1 Honda ECUs.
DAC
Digital to Analog Converter. the process of taking a digital value and converting it to an analog signal of some variety...
Data Link Connector (DLC) Communication Protocols
Technical specifications of the Honda OBD1 Data Link Connector (DLC) communication protocol, voltage levels, capacitance...
Dec At Addy
Dec At Addy is the decimal equivalent of the hex value at the specified address or location. So if the address was 1094h...
Disable VTEC VSS Check P28
Author: Gimpy Accord Date: 081403 03:42 1286 C5 22 19 : SB 22.1 1289 C5 F3 C0 32 : CMPB F3, 32 128D CA 1B : JLT 12AA 128...
Disable VTEC VSS Check P30 203
Author: doc 071003 15:21 Did i? Ok, in a 203 or 209 rom, you can change the location 6010 (hex) from 00 to FF to bypass...
Disable VTEC VSS Check P72
How to disable 25mph VSS check for VTEC engagement on P72: Author: Speedz Date: 082303 15:59 here's where its at in the...
DIY Datalogging Cable via Nokia FBUS Modification
Technical guide to converting a legacy Nokia FBUS serial phone cable into a low-cost USB-to-TTL serial adapter for OBD1...
DIY Easy-RTP v1.0 build and installation guide
Archived assembly guide and partial OBD0/OBD1 installation notes for the DIY Easy-RTP v1.0 board.
ECU
The engine control unit reads the sensors and drives fuel, ignition and idle on Honda PGM-FI engines.
ECU Chipping Wirelist
Pin connections and traces between the MCU, latch, and external EPROM socket on OBD1 Honda ECUs.
ECU Definition Codes
A reference table of Honda and Acura OBD0, OBD1, and OBD2 ECU part numbers, their markets, and corresponding code design...
ECU Hardware
Inside a Honda ECU: the boards, chips and circuits.
ECU Sensors
The input sensors a Honda ECU reads to run fuel and ignition.
EETools ChipMax Device Programmer
Technical specifications, software configuration, and chip settings for the EETools ChipMax USB device programmer.
Electronic Part Supplier
a handful of major electronic part suppliers: Digikey good instock availability, great catalog, good website.
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