M50FW040
Firmware hub (FWH) interface Configuration Registers
6.1.3
Lock Down
The Lock Down Bit provides a mechanism for protecting software data from simple hacking
and malicious attack. When the Lock Down Bit is set, ‘1’, further modification to the Write
Lock, Read Lock and Lock Down Bits cannot be performed. A reset or power-up is required
before changes to these bits can be made. When the Lock Down Bit is reset, ‘0’, the Write
Lock, Read Lock and Lock Down Bits can be changed.
6.2
Firmware Hub (FWH) General-Purpose Input Register
The Firmware Hub (FWH) General Purpose Input Register holds the state of the Firmware
Hub Interface General Purpose Input pins, FGPI0-FGPI4. When this register is read, the
state of these pins is returned. This register is read-only and writing to it has no effect.
The signals on the Firmware Hub Interface General Purpose Input pins should remain
constant throughout the whole Bus Read cycle in order to guarantee that the correct data is
read.
6.3
Manufacturer Code Register
Reading the Manufacturer Code Register returns the manufacturer code for the memory.
The manufacturer code for STMicroelectronics is 20h. This register is read-only and writing
to it has no effect.
6.4
Device Code Register
Reading the Device Code Register returns the device code for the memory, 2Ch. This
register is read-only and writing to it has no effect.
6.5
Firmware Hub (FWH) General-Purpose Input Register
The Firmware Hub (FWH) General Purpose Input Register holds the state of the Firmware
Hub Interface General Purpose Input pins, FGPI0-FGPI4. When this register is read, the
state of these pins is returned. This register is read-only and writing to it has no effect.
The signals on the Firmware Hub Interface General Purpose Input pins should remain
constant throughout the whole Bus Read cycle in order to guarantee that the correct data is
read.
6.6
Manufacturer Code Register
Reading the Manufacturer Code Register returns the manufacturer code for the memory.
The manufacturer code for STMicroelectronics is 20h. This register is read-only and writing
to it has no effect.
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