Eccel Technology Ltd BIORADRDR0200 Manual Do Utilizador
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4.3 Power Down Mode
The Power Down functionality is provided via the nPWRDN pin. This pin is configured as an input without any pull-up
or pull-down resistors, thus it must be driven by the user. For normal operation, this pin should be connected to VCC
or driven high. After the user drives this pin low the system prepares to go into Power Down Mode and drives nBUSY
line low just before entering this state. To wake up module the nPWRDN pin must be driven high. The module will
restart and drive the nBUSY line low to inform the user that it is starting the system again. When start-up is
completed, the nBUSY line is driven high. During the restart, none of the volatile memory content is retained.
or pull-down resistors, thus it must be driven by the user. For normal operation, this pin should be connected to VCC
or driven high. After the user drives this pin low the system prepares to go into Power Down Mode and drives nBUSY
line low just before entering this state. To wake up module the nPWRDN pin must be driven high. The module will
restart and drive the nBUSY line low to inform the user that it is starting the system again. When start-up is
completed, the nBUSY line is driven high. During the restart, none of the volatile memory content is retained.
The reaction time of the system will vary depending upon the active configuration and the following:
• Communication – if the line is pulled low whilst there is ongoing communication, then the Power Manager
will wait until communication is finished before going into the Power Down state.
• Command execution – if the line is pulled low whilst the system is executing a command, then the Power
Manager will wait until command execution is finished before going into the Power Down state.
When the module is in the Power Down state, all systems are turned-off and all IOs are in a high impedance state.
The module won’t respond to any signals or communication coming from outside.
The module won’t respond to any signals or communication coming from outside.
4.4 Memory Locking
The module has an option to lock its memory using an 8-byte long password. The default state of the module after
power-up is locked and the default password is all bytes equal to 0x00. The user cannot see the memory content
when the module is locked, and any write to the memory will be discarded. During the unlock procedure, the
content of the non-volatile memory is copied to the volatile memory and is available for reading and writing.
Changes made in volatile memory are updated in non-volatile memory during the lock procedure. Commands using
data from this memory range use the volatile memory when the module is unlocked and non-volatile memory when
the module is locked
power-up is locked and the default password is all bytes equal to 0x00. The user cannot see the memory content
when the module is locked, and any write to the memory will be discarded. During the unlock procedure, the
content of the non-volatile memory is copied to the volatile memory and is available for reading and writing.
Changes made in volatile memory are updated in non-volatile memory during the lock procedure. Commands using
data from this memory range use the volatile memory when the module is unlocked and non-volatile memory when
the module is locked