For example, assume input 2 is programmed active high and power control and
the wire harness has an active high dash switch connected to this input. Now
assume we change the active state of this input from high to low and download
this new logic to the module. The module will receive the new logic and
immediately after download will turn off (assuming input 2 is the only active
power control input during the download). The module will not turn on again until
the signal to the input 2 pin is physically rewired such that it switches ground
instead of battery.
Note: Changing power control settings on a VMM1210 may prevent you from
being able to wake up the VMM unless you make corresponding changes to
your wire harness and/or input connection arrangement.
3.2. Addressing Digital Inputs
Digital inputs ADDR1, ADDR2, ADDR3, ADDR4 and ADDR5 are dedicated
address inputs. These inputs are used to set the system address on the module
such that it is unique among all other modules in the system. The maximum
allowable addresses in a VMM system is 31 including all devices on the bus
(VMMs, PGM, LIMs, etc.).
These inputs are all active-low inputs with internal pull-up resistors. The inputs
are read when the module starts to indicate which portion of ladder logic the
module is to run. The state of these inputs must be valid before turning the VMM
on. It is recommended that these inputs be permanently grounded (depending on
desired address) in the vehicle harness to ensure a valid state before power up.
The addressing arrangement is shown in the following table, which shows the
required inputs that need to be active and floating (active shown as 1, floating
shown as 0).
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