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How to fix your Innovate LC-1
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WolfDK Offline
Boost addicted Volvo freak
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Joined: Aug 2010
Post: #1
How to fix your Innovate LC-1
So my Innovate LC-1 also reached its programmed end of life.

Well after disassembling the unit i figured the hardware was ok.
After reprogramming the firmware using the ICSP header inside
my LC-1 is back online, but why did it go bad the first time ?

Reading the Atmega64 MCU datasheet it becomes clear that
Innovate takes no measures against undervoltage and transients
reaching the MCU and effectively glitching it. The Atmel Atmega64
datasheet clearly states that precautions MUST be taken to
ensure that the MCU is reset doing such conditions. If no action is
taken the result is corrupted flash memory (corrupted firmware),
this is exactly what makes the LC-1 behave erratic or go completly
dead.

*glitching = Causing a CPU to behave in a way not intended by
its designers.

How to fix the issue:
Use a voltage supervisor like TL7757 to pull the reset pin low, it
actually fits straight into the first 3 holes of the ICSP header inside
the LC-1, and its pin compatible with header Smile

LC-1 ICSP header pinout:

1: GND (Square pad)
2: VCC
3: Reset
4: SCK
5: PE1/MISO
6: PE0/MOSI

TL7757 pinout (pins down, facing writing):

1: Reset
2: VCC
3: GND

Mounting the TL7757 will prevent future firmware corruption,
ensure a correct AFR reading and preventing your baby
blowing up due to erratic or plain wrong AFR feedback.
Warranty will of cause be void, but getting a replacement LC-1
will NOT fix this issue, your new unit will have the same design
flaw!

Extracting the firmware:

To extract a firmware suitable for programming i used the Linux
command dd: dd if=[original_fw.bin] of=ICSP_fw.bin bs=1
skip=32

original_fw.bin = LC-1 firmware from Innovate.

Converting firmware from bin to hex:

avr-objcopy -I binary -O ihex ICSP_fw.bin ICSP_fw.hex

Programming the firmware using ICSP:

To reprogram the unit i used a DAPA programmer and UISP from
the Ubuntu repository.
Programming instructions using Linux

I will update the article with more details like images and a firmware
that can be written using ICSP, until then this is all you get.

- Enough boost is a fine balance between fun and flying parts
10-18-2013 10:14 PM
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Coupe' de Tat Offline
bourbon the other foodgroup
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Posts: 6,968
Joined: Aug 2010
Post: #2
RE: How to fix your Innovate LC-1
check out the brain on this one... how the hell do you figure all of this stuff out?
10-19-2013 10:10 AM
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