FT90x Memory Organization

Program memory

The core processor contains the 256kB of program memory. The first 144 bytes in the Program Memory contains the following :

Reset vector,
Watchdog vector,
32 interrupt vectors,
1 non-maskable interrupt vector (reserved for the debugger),
Program entry point.

Address Function

0x00 Reset vector.

0x04 Watchdog vector.

0x08 Interrupt vector 0.

0x0C Interrupt vector 1.

... ...

0x80 Interrupt vector 30.

0x84 Interrupt vector 31.

0x88 Interrupt vector 32 (NMI).

0x8C Program entry point.

Address	Function
0x00	Reset vector.
0x04	Watchdog vector.
0x08	Interrupt vector 0.
0x0C	Interrupt vector 1.
...	...
0x80	Interrupt vector 30.
0x84	Interrupt vector 31.
0x88	Interrupt vector 32 (NMI).
0x8C	Program entry point.

FT90x Program Memory Organization

Flash memory

The internal Flash memory is used to store a boot loader or user application of the FT90x.

Upon reset, CPU is held in reset state and the boot controller has control of both Flash memory bus and program memory bus.
It copies the contents of Flash memory into program memory automatically, and then releases both interfaces. At this point, the CPU is released from reset and PC points to address 0 for both memories.

Data memory

The data memory is organized as a linear block of RAM memory with maximal capacity of 64 kB.

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