Freescale Semiconductor SC140 specifications Execution State, Reset Processing State

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Processing States

Table 5-17. Processing State Transitions

Processing State Transitions

Description

 

 

 

 

1, 2, 3, 4

Assertion of one of the core hardware reset

 

input signals.

 

 

 

 

5

De-assertion of reset if EE0 or a JTAG debug

 

command is asserted during reset

 

 

6, 7

Entering debug state through an external

 

request (JTAG, EE pin or system input).

 

 

8

Entering debug state through execution of

 

debug/debugev, or occurrence of EOnCE

 

events as programmed in the activated

 

EOnCE, or an external request ((JTAG, EE pin

 

or system input)

 

 

9

Executing the STOP instruction.

 

 

10

Executing the WAIT instruction.

 

 

11

De-assertion of the reset signal, assuming

 

EE0 not asserted.

 

 

12

Assertion of one of the exit from STOP signals.

 

 

13

Assertion of an unmasked interrupt request.

 

 

14

Programming change to the EOnCE control

 

registers through the JTAG.

 

 

5.7.3 Execution State

The execution state is where instructions are repeatedly fetched and executed. All software runs in the execution state.

5.7.4 Reset Processing State

The reset processing state is entered when an external core hardware reset occurs. Upon entering the reset state, the following registers are updated with their reset values:

SR

EMR

VBA

MCTL

Refer to Chapter 3, “Control Registers,” for details on the reset of the various bits of the above registers.

The core remains in the reset state until the end of hardware reset. Upon leaving the reset state, the core enters the exception working mode, as part of the execution state, and program execution begins at a derivative-dependent program memory address.

SC140 DSP Core Reference Manual

5-43

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Freescale Semiconductor SC140 specifications Execution State, Reset Processing State, Processing State Transitions