ETK-V1.1 - User’s Guide
29
ETAS
Hardware Description
4.12.3
External Watchdog disable
The ETK-V1.1 provides a method to disable an external watchdog circuit on the
ECU during braindead flashing.
The watchdog disable control signal in available on the VertiCal connector on
signal TOOL_IO0 (Pin L22). This signal is routed directly to a ball of the VertiCal
base board, completely bypassing the microcontroller on the VertiCal base
board.
When the ETK-V1.1 is configured to use this signal (Configuration parameter
"Use VertiCal TOOL_IO0 as Watchdog" set to "Yes"), the signal TOOL_IO0 is set
to logic high during brain dead flashing with the appropriate ProF command.
When "Use VertiCal TOOL_IO0 as Watchdog" is set to "No", the TOOL_IO0 pin
is not driven by the ETK-V1.1 (high-Z).
See chapter "Nexus Interface" on page 25 for details about the disable watch-
dog logic circuit.
4.13
Reset
The requirement for ETK reset mechanism is to ensure that power-up and
power-down behavior of ECU is clean and smooth and to prevent corruption of
data stored in the ETK.
To accomplish this the ETK-V1.1 senses the VDDE2/3 of the ECU. This allows it
to detect when the ECU is off and forward this information to INCA. In addition,
it allows the ETK to enter the power save mode with the CAL tool (ES590/ES591)
unplugged. In addition, the ETK-V1.1 senses the status of the /RESET and /
RSTOUT lines to generate a write protect signal for its memory. Finally, the ETK-
V1.1 generates a reset signal by pulling /RESET to keep the ECU in reset while the
ETK is in power save mode and to prevent the
μ
C from starting until the ETK is
ready to work. The ETK is ready to work when it has has finished its initialization
after leaving power save mode or after initial power-up. This feature allows it
also to reset the ECU under tool control (required for INCA and ProF) and to
perform an emergency stop of the ECU in case of ETK failure.
PLLCFG0
PLLCFG1
Clock Mode
0
0
Bypass Mode
0
1
External Reference (Oscillator)
1
0
Crystal Reference
1
1
1:1 Mode
