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1 reset processing, Reset processing – FUJITSU FR family 32-bit microcontroller instruction manuel CM71-00101-5E User Manual

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CHAPTER 4 RESET AND "EIT" PROCESSING

4.1

Reset Processing

A reset is a means of forcibly terminating the currently executing process, initializing
the entire device, and restarting the program from the beginning. Resets are used to
start the LSI operating from its initial state, as well as to recover from error conditions.

Reset Operations

When a reset is applied, the CPU terminates processing of the instruction executing at that time and goes

into inactive status until the reset is canceled. When the reset is canceled, the CPU initializes all internal

registers and starts execution beginning with the program indicated by the new value of the program

counter (PC).

Initialization of CPU Internal Register Values at Reset

When a reset is applied, the FR family CPU initializes internal registers to the following values.

PC:

Word data stored at address "000FFFFC

H

"

ILM: "01111

B

"

T Flag:

"0" (trace OFF)

I Flag:

"0" (interrupt disabled)

S Flag:

"0" (use SSP pointer)

TBR: "000FFC00

H

"

SSP: "00000000

H

"

R00 to R14:

Undefined

R15: SSP

For a description of built-in functions following a reset, refer to the Hardware Manual provided with each

FR family device.

Reset Priority Level

Resets have a higher priority than all "EIT" operations.