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Thread: 8051 lt1 mode 4 commands

  1. #1
    Fuel Injected!
    Join Date
    Mar 2013
    Posts
    1,475

    8051 lt1 mode 4 commands

    Found from a definition file with unknown author.
    Some are tested and working



    the format of the Mode 4 command to PCM is described below. 12 data bytes are used.
    ;byte 1 028a enable control
    ;; b0 AC Clutch
    ;; b1 AIR Pump
    ;; b2 Fan1
    ;; b3 Fan2
    ;; b4 CCPDC
    ;; b5 set what m001b-m0041=128
    ;; b6 extend IAC
    ;; b7 set BLM? set cell#?
    ;;byte 2 028b control command for 028a
    ;; b0 AC Clutch
    ;; b1 AIR Pump
    ;; b2 Fan1
    ;; b3 Fan2
    ;; b4 CCPDC on/off
    ;;byte 3 028c enable control
    ;; b0 007e b1 ?
    ;; b1 0080 b3 SkipShift?
    ;; b2 MIL?
    ;; b3 007e b2 ?
    ;; b4 tes_2 b3
    ;; b5 tes_2 b2
    ;;byte 4 028d control command for 028c
    ;;byte 5 028e enable control
    ;; b0 TCC Enable
    ;; b1 TCC Ctrl
    ;; b2 shift sol - Gear
    ;; b3 shift sol - Gear
    ;; b4 zero trans adapts
    ;; b5 BLM update
    ;; b6 Closed Loop
    ;; b7 IAC PID
    ;;byte 6 028f control command for 028e
    ;; b0 TCC Enable
    ;; b1 TCC Ctrl
    ;; b2 Gear b0
    ;; b3 Gear b1
    ;; b4 preload trans adapts
    ;; b5 BLM update enable/disable
    ;; b6 Closed Loop enable/disable
    ;; b7 IAC PID enable/disable
    ;;byte 7 0290 select PWM 1 control
    ;; b0 LinePressure enable
    ;; b1 32DSS enable
    ;; b2 EGRDC enable
    ;; b3 something enable, disable EGR override
    ;; b4 IAC enable
    ;; b5 IAC 1=RPM,0=steps
    ;; b6 AFR command
    ;; b7 Cylinder Fuel Cut enable
    ;;byte 8 0291 PWM 1 Command Duty Cycle (LinePress, 32DSS, EGR)
    ;;byte 9 0292 IAC Command
    ;;byte 10 0293 AFR Command, CylNumToCut
    ;;byte 11 0294 select PWM 2 control
    ;; b0 SpkControl enable
    ;; b1 SpkCmd 1=Ret, 0=Adv
    ;; b2 SpkCmd 1=Delta, 0=Absolute
    ;; b3 CCP enable
    ;;byte 12 0295 PWM 2 Command Duty Cycle (CCPDC, SpkAdv)

    hex to bin 0 0 0 0 0 0 0 0
    b7 b6 b5 b4 b3 b2 b1 b0

    (afr x 10) to hex
    (%dc x 2.55) to hex
    (rpm x 0.08) to hex
    (counts x 1) to hex
    (spark degree x 1) to hex

    SAMPLE COMMANDS

    CLEAR MODE 4 EFFECT
    F4 62 04 00 00 00 00 00 00 00 00 00 00 00 00

    AFR 12.8
    F4 62 04 00 00 00 00 00 00 40 00 00 80 00 00

  2. #2
    LT1 specialist steveo's Avatar
    Join Date
    Aug 2013
    Posts
    4,040
    wow good find! i was aware of some of those mode 4 commands, but not afr and spark? and i thought IAC could only be set RPM target

    that's going to be very helpful

  3. #3
    Fuel Injected!
    Join Date
    Mar 2013
    Posts
    1,475
    Here are some more sample commands and explanation.
    At the end of the command is added checksum byte.


    If anyone can help
    I need,
    commands for BLM reset,
    memory write command( i guess it exist),
    MODE 5 commnand - motor rehome ,for abs delphi vi modul used in f-body 93-97 and other old gm cars
    it is very useful for bleeding brakes

    delphi abs vi
    MODE F5: MOTOR REHOME - in this mode the tech 1 commands the EBCM to rehome the motors on the hydrauic modulator/master cylinder assembly. this mode should ALWAYS be used prior to bleeding the brake system.





    f4 62 04 +
    __________________________________
    Spark retard delta
    00 00 00 00 00 00 00 00 00 00 07 xx
    spark retard absolute
    00 00 00 00 00 00 00 00 00 00 03 xx
    spark advence delta
    00 00 00 00 00 00 00 00 00 00 05 xx
    spark advance absolute
    00 00 00 00 00 00 00 00 00 00 01 xx
    xx=spark degree [ (spark degree x 1) to hex ]
    __________________________________
    ccp enable dc
    00 00 00 00 00 00 00 00 00 00 08 xx
    xx=%dc [ (%dc x 2.55) to hex ]
    __________________________________
    afr command
    00 00 00 00 00 00 40 00 00 xx 00 00
    xx=afr -> 12.0 = $78, 12.5 = $7d, 12.8 = $80, 13.0 = $82, 13.2 = $84, 13.5 = $87, 15.0 = $96, 15.5 = $9b, 16.0 = $a0, 16.5 = $a5, 17.0 = $aa
    __________________________________
    open loop
    00 00 00 00 40 00 00 00 00 00 00 00
    blm freeze update
    00 00 00 00 20 00 00 00 00 00 00 00
    ccp disable
    10 00 00 00 00 00 00 00 00 00 00 00
    open loop + disable blm update + ccp disable
    10 00 00 00 60 00 00 00 00 00 00 00
    open loop + disable blm update + ccp disable + afr 12.8
    10 00 00 00 60 00 40 00 00 80 00 00
    open loop + disable blm update + ccp disable + afr 12.8 +delta spark advance
    10 00 00 00 60 00 40 00 00 80 05 xx
    xx=delta spark advance [ (spark degree x 1) to hex ]
    ___________________________________

    trans control 1st gear
    00 00 00 00 0C 0C 00 00 00 00 00 00
    trans control 2nd gear
    00 00 00 00 0C 04 00 00 00 00 00 00
    trans control 3rd gear
    00 00 00 00 0C 00 00 00 00 00 00 00
    trans control 4th gear
    00 00 00 00 0C 08 00 00 00 00 00 00

    Delta Spark Advance/Retard is added to all other spark components (base spark, warmup, knock, trac control, etc).
    Absolute Spark command, will completely overrides
    ALL spark components, until the mode4 command is stopped
    _________________________________________

    MODE 3 memory dump command
    $F4,$58,$03,$xx,$xx
    $xx,$xx= memory address
    memory address 001c= $00,$1c
    _____________________________________________
    Transmission adapt learned pressure modifier values

    memory (T side)
    $1830 - $1840 Gear 2 Adapt Cells 0-16
    $1841 - $1851 Gear 3 Adapt Cells 0-16

    Automatic Transmission Adapt Learned Pressure Modifier Values
    are output in mode1 message 6, along with a couple variables. To get the
    adapt cell values (memory $1830 to $1840 for 2nd gear cells 0-16 & memory $1841 to $1851 for 3rd gear cells 0-16), use this memory dump command.
    look in the comm window to see the request & the returned adapt values
    the adapt value is the 4th byte of the Recv data.
    convert to psi if needed, psi = N *.125 -16
    $80 is 0 psi
    $00 is -16 psi
    $FF is 16


    _________________________________________________
    mode 3 blm
    Left BLMs $001c thru $002e
    Right BLMS $002f thru $0041
    $F4,$58,$03,$xx,$xx
    look in the comm window to see the request & the returned values


    __________________________________________________ ___________________

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