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OBD Analyser NG

Next-generation handheld with graphical display, ARM Cortex M3 controller and Open Source user interface

OBD Analyser NG

The compact OBD2 Analyser in the June 2007 issue was an enormous success — not surprising for an affordable handheld onboard diagnostics device with automatic protocol recognition and error codes explained in plain language. Now enhanced with a graphical display, Cortex M3 processor and an Open Source user interface, the next generation of Elektor’s standalone analyser sets new standards for a DIY OBD2 project.

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Hardware Handheld Analyser:
• Full graphics display 132 x 32 pixels
• RGB backlighting
• Convenient four press button control
• Power supply taken from onboard diagnostics port (12 V car battery)
• Uses standard OBD cable
• Convenient size (126 mm wide x 68 mm tall x 25 mm deep)
• Weight approx. 110 g

Hardware and software DX module (DXM-PCB):
• Hardware for onboard OBD2 control
• Firmware for onboard OBD2 control
• 3V3 tx-rx level
• Cortex M3 CPU (32-bit controller)
• 72 MHz internal clock rate
• Onboard 3V3 power supply for external device – max. 55mA
• Jumperless
• Bootloader
• LED indicators for onboard Connect and Data Stream
• Analogue battery voltage measurement
• AT control set
• Supports all currently implemented protocols: PWM, VPWM, ISO9141-2, ISO14230-4 (KWP2000), ISO15765-4 (CAN, 11/29 Bit , 250/500 kBaud)
• Firmware update via ISP interface
• Rapid OBD connection

Open Source firmware functions:
• Graphical user control interface display
• Selection of vehicle data, PID list, error code list, VIN, MIL status
• Selection menu for active transmission control system (for vehicles with multiple transmission options, e.g. automatic gearbox)
• Saved error store (freeze-frames) for previous faults
• Expandable memory bank for sample error codes
• Erasable error store
• Live display of sensor data
• Acoustic signals
• Selection menu for scan mode (automatic or manual)
• Menu text in English
• Choice of direction (rotatable through 180 degrees)
• Controllable RGB backlight brightness
• Battery voltage measurement

Expansion options:
• USB port for data transfer or supporting use with PC
• Real-time clock (RTC) for data recording (e.g. time and date stamping)
• Adequate checklist flash memory (1, 2 or 4 MByte) for data logging functions

Open Source:
• Open Source firmware for the controller
• ISP interfaces accessible for AT90CAN128 and AT90USB162
• Other firmware can be substituted if required
• Demo firmware for ‘Speedometer with warning functions’
SMD components (prefitted on board):
C1,C2 = 22pF
C3,C4 = 100nF
C5,C6,C11–C18 = 1µF
R1 = 10kOhm
R2,R3 = 1Ohm
R4 = 1kOhm
R5,R6 = 1.5kOhm
R7,R10,R13 = 110Ohm
R8,R11,R14 = 68Ohm
R9,R12,R15 = 47Ohm
R16 = 330Ohm
R17 = 33Ohm
R18,R19 = 4.7kOhm
Q1 = 8MHz quartz crystal
D1 = 1N4007
D2 = B0530WS
D3 = 1N4148
T1,T2,T3 = BCR108
IC1 = LD1117 3V3
IC2 = MC34063
IC3 = AT90CAN128
LED1,LED2,LED3 = RGB LED, Kingbright type KAA-3528SURKVGAPBA

Components to be fitted separately:
DSP1 = LCD 132 x 32
DXM = OBD module
J1,J2 = 10-way SIL pinheader
J3 = 2-way pinheader
L1 = 220µH (choke coil)
LS1 = miniature loudspeaker
S1–S4 = pushbutton
SV1 = 10-way boxheader
X1 = 9-pin sub-D plug with solder buckets

Fastenings and accessories:
4 x pushbutton plungers
4 x case screws
5 x PCB screws
Cardboard packaging
Case with front panel
Sub-D connector fixings
Standard OBD2 cable

Sources of supply:
Component set # 090451-71 available from the Elektor Shop contains all necessary components and the PCB with SMD components pre-fitted together with the case (with custom front overlay), fixings and the standard OBD2 cable. See Elektor Shop pages.
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