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-   -   Stock Chip Serial # for Bosch ECU 0 261 200 473? (https://rennlist.com/forums/964-forum/564739-stock-chip-serial-for-bosch-ecu-0-261-200-473-a.html)

993PET 04-27-2010 11:52 PM
Stock Chip Serial # for Bosch ECU 0 261 200 473?
 
What Stock Chip Serial # Range should I be looking for? Bosch
ECU 0 261 200 473 (94' C2)

Thanks,

JF

joey bagadonuts 04-28-2010 12:29 AM
1 Attachment(s)
Joseph,

Kinda' cutting it close. Race is only a few weeks away. :)

Good question. Some of the chips are interchangeable but the majority are not. It also looks like you can use a couple of different stock chips with your particular ECU. You may want to post your search here--lots of folks have switched to an aftermarket item. You can also use a Steve Wong or other aftermarket chip since you're running Prepared H, right?

993PET 04-28-2010 03:22 AM
Joey:

Thanks, that's the info I was looking for, this is for my 94' Cab that I'm returning to stock from an Autothority MAF. Is the "Chksum" relevant? If so where can I find it for my ecu?

I have a Steve Weiner-Rennsport Systems 100 octane race gas chip for the race car.

JF

joey bagadonuts 04-28-2010 09:00 AM
Ah yes, you have two 964's. Sounds like you've got the race car covered. Have you raced the 964, yet? Last time I saw you at Gingerman, I think you were still campaigning a water-cooled example.

As for the "Chksum," I'm not sure what that is and whether it makes a difference. Anyone?

Steve Weiner-Rennsport Systems 04-28-2010 01:06 PM
The Checksum is only relevant to a person making a chip and you cannot find it without an EPROM burner.

Its a way for us to ensure that the chip will start the car,...:) :)

jmreiser 04-28-2010 04:31 PM
In computer programming generally, a checksum is one simple means of ensuring that the data was probably not garbled during the chip making process or later. A simple checksum is literally the sum of all the data bytes. You add them up and ignore overflow, just let it wrap around. If that number matches one that was stored during programming, then the odds are pretty high that nothing changed. We could checksum this paragraph of text by adding up all the letters' ASCII value (each letter has a numeric value), and if it matches, then Rennlist did not lose data on its server, nor in transmission over the internet.

JasonAndreas 04-28-2010 08:38 PM
Code:
; Calculate EPROM Checksum 0x0000 - 0x7EFE
MEM_EXT:40AF
MEM_EXT:40AF CALCULATE_CHECKSUM:                   
MEM_EXT:40AF                mov    P2, #0xF4 ; '('
MEM_EXT:40B2                movx    A, @R0          ; F400
MEM_EXT:40B3                xrl    A, #1001111b
MEM_EXT:40B5                mov    RAM_20, A
MEM_EXT:40B7                jb      SWITCH_DEBUG, @@5 ; RAM_20.3
MEM_EXT:40B7
MEM_EXT:40BA                mov    P2, #0x7E ; '~'
MEM_EXT:40BD                mov    R0, ERROR_SYSTEM ; 7EB8
MEM_EXT:40BF                movx    A, @R0
MEM_EXT:40C0                jb      ACC.7, @@5
MEM_EXT:40C0
MEM_EXT:40C3                mov    R3, #0
MEM_EXT:40C5                mov    R2, #0x7F ; ''
MEM_EXT:40C7                mov    DPTR, #0        ; Calculate Checksum
MEM_EXT:40CA                clr    A
MEM_EXT:40CB                mov    R0, A
MEM_EXT:40CC                mov    R1, A
MEM_EXT:40CD
MEM_EXT:40CD @@1:                                   
MEM_EXT:40CD                                       
MEM_EXT:40CD                clr    A
MEM_EXT:40CE                movc    A, @A+DPTR
MEM_EXT:40CF                add    A, R0
MEM_EXT:40D0                mov    R0, A
MEM_EXT:40D1                jnc    @@2
MEM_EXT:40D1
MEM_EXT:40D3                inc    R1
MEM_EXT:40D4
MEM_EXT:40D4 @@2:                                   
MEM_EXT:40D4                inc    DPTR
MEM_EXT:40D5                jb      TCON.1, @@5   
MEM_EXT:40D5
MEM_EXT:40D8                mov    A, DPH
MEM_EXT:40DA                cjne    A, RAM_2, @@1
MEM_EXT:40DA
MEM_EXT:40DD                mov    RAM_6F, #0x46 ; 'F'
MEM_EXT:40E0                mov    A, DPL
MEM_EXT:40E2                cjne    A, RAM_3, @@1
MEM_EXT:40E2
MEM_EXT:40E5                clr    A
MEM_EXT:40E6                movc    A, @A+DPTR
MEM_EXT:40E7                clr    C
MEM_EXT:40E8                subb    A, R1
MEM_EXT:40E9                jnz    @@3
MEM_EXT:40E9
MEM_EXT:40EB                inc    DPTR
MEM_EXT:40EC                movc    A, @A+DPTR
MEM_EXT:40ED                clr    C
MEM_EXT:40EE                subb    A, R0
MEM_EXT:40EF                jnz    @@3
MEM_EXT:40EF
MEM_EXT:40F1                clr    PSW.5
MEM_EXT:40F3                sjmp    @@4
MEM_EXT:40F3
MEM_EXT:40F5 ; ---------------------------------------------------------------------------
MEM_EXT:40F5
MEM_EXT:40F5 @@3:                                   
MEM_EXT:40F5                                       
MEM_EXT:40F5                setb    PSW.5
MEM_EXT:40F7
MEM_EXT:40F7 @@4:                                   
MEM_EXT:40F7                mov    R0, ERROR_SYSTEM
MEM_EXT:40F9                movx    A, @R0          ; 7EB8
MEM_EXT:40FA                setb    ACC.7
MEM_EXT:40FC                movx    @R0, A
MEM_EXT:40FD                mov    DPTR, #RAM_EXT_6266
MEM_EXT:4100                mov    A, #63
MEM_EXT:4102                mov    RAM_RPM_VALUE, A
MEM_EXT:4104                movc    A, @A+DPTR      ; 62A5 = Fault Code 41 Control unit faulty
MEM_EXT:4105                mov    B, A
MEM_EXT:4107                mov    R2, #4
MEM_EXT:4109                clr    A
MEM_EXT:410A                mov    R6, A
MEM_EXT:410B                mov    R7, A
MEM_EXT:410C                mov    C, PSW.5
MEM_EXT:410E                lcall  STORE_FAULT_CODE

Indycam 04-28-2010 09:43 PM
Originally Posted by JasonAndreas (Post 7523472)
Code:
; Calculate EPROM Checksum 0x0000 - 0x7EFE
MEM_EXT:40AF
MEM_EXT:40AF CALCULATE_CHECKSUM:                   
MEM_EXT:40AF                mov    P2, #0xF4 ; '('
MEM_EXT:40B2                movx    A, @R0          ; F400
MEM_EXT:40B3                xrl    A, #1001111b
MEM_EXT:40B5                mov    RAM_20, A
MEM_EXT:40B7                jb      SWITCH_DEBUG, @@5 ; RAM_20.3
MEM_EXT:40B7
MEM_EXT:40BA                mov    P2, #0x7E ; '~'
MEM_EXT:40BD                mov    R0, ERROR_SYSTEM ; 7EB8
MEM_EXT:40BF                movx    A, @R0
MEM_EXT:40C0                jb      ACC.7, @@5
MEM_EXT:40C0
MEM_EXT:40C3                mov    R3, #0
MEM_EXT:40C5                mov    R2, #0x7F ; ''
MEM_EXT:40C7                mov    DPTR, #0        ; Calculate Checksum
MEM_EXT:40CA                clr    A
MEM_EXT:40CB                mov    R0, A
MEM_EXT:40CC                mov    R1, A
MEM_EXT:40CD
MEM_EXT:40CD @@1:                                   
MEM_EXT:40CD                                       
MEM_EXT:40CD                clr    A
MEM_EXT:40CE                movc    A, @A+DPTR
MEM_EXT:40CF                add    A, R0
MEM_EXT:40D0                mov    R0, A
MEM_EXT:40D1                jnc    @@2
MEM_EXT:40D1
MEM_EXT:40D3                inc    R1
MEM_EXT:40D4
MEM_EXT:40D4 @@2:                                   
MEM_EXT:40D4                inc    DPTR
MEM_EXT:40D5                jb      TCON.1, @@5   
MEM_EXT:40D5
MEM_EXT:40D8                mov    A, DPH
MEM_EXT:40DA                cjne    A, RAM_2, @@1
MEM_EXT:40DA
MEM_EXT:40DD                mov    RAM_6F, #0x46 ; 'F'
MEM_EXT:40E0                mov    A, DPL
MEM_EXT:40E2                cjne    A, RAM_3, @@1
MEM_EXT:40E2
MEM_EXT:40E5                clr    A
MEM_EXT:40E6                movc    A, @A+DPTR
MEM_EXT:40E7                clr    C
MEM_EXT:40E8                subb    A, R1
MEM_EXT:40E9                jnz    @@3
MEM_EXT:40E9
MEM_EXT:40EB                inc    DPTR
MEM_EXT:40EC                movc    A, @A+DPTR
MEM_EXT:40ED                clr    C
MEM_EXT:40EE                subb    A, R0
MEM_EXT:40EF                jnz    @@3
MEM_EXT:40EF
MEM_EXT:40F1                clr    PSW.5
MEM_EXT:40F3                sjmp    @@4
MEM_EXT:40F3
MEM_EXT:40F5 ; ---------------------------------------------------------------------------
MEM_EXT:40F5
MEM_EXT:40F5 @@3:                                   
MEM_EXT:40F5                                       
MEM_EXT:40F5                setb    PSW.5
MEM_EXT:40F7
MEM_EXT:40F7 @@4:                                   
MEM_EXT:40F7                mov    R0, ERROR_SYSTEM
MEM_EXT:40F9                movx    A, @R0          ; 7EB8
MEM_EXT:40FA                setb    ACC.7
MEM_EXT:40FC                movx    @R0, A
MEM_EXT:40FD                mov    DPTR, #RAM_EXT_6266
MEM_EXT:4100                mov    A, #63
MEM_EXT:4102                mov    RAM_RPM_VALUE, A
MEM_EXT:4104                movc    A, @A+DPTR      ; 62A5 = Fault Code 41 Control unit faulty
MEM_EXT:4105                mov    B, A
MEM_EXT:4107                mov    R2, #4
MEM_EXT:4109                clr    A
MEM_EXT:410A                mov    R6, A
MEM_EXT:410B                mov    R7, A
MEM_EXT:410C                mov    C, PSW.5
MEM_EXT:410E                lcall  STORE_FAULT_CODE
Well yes of course , that goes without saying .

Lorenfb 04-29-2010 12:01 AM
"Its a way for us to ensure that the chip will start the car,"

Actually, the engine will start with an incorrect checksum, but will produce
a fault code in the DME:

movc A, @A+DPTR ; 62A5 = Fault Code 41 Control unit faulty

and then;

lcall STORE_FAULT_CODE

Steve Weiner-Rennsport Systems 04-29-2010 05:00 AM
Not always,......

OBD-2 cars will generally not start with incorrect checksums.

BTDT,...:)


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