Samsung S3F80JB manual DI Disable Interrupts, Operation SYM 0 ←, No flags are affected

Models: S3F80JB

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S3F80JBINSTRUCTION SET

DI — Disable Interrupts

DI

Operation: SYM (0) 0

Bit zero of the system mode control register, SYM.0, is cleared to "0", globally disabling all interrupt processing. Interrupt requests will continue to set their respective interrupt pending bits, but the CPU will not service them while interrupt processing is disabled.

Flags:

No flags are affected.

 

 

 

Format:

 

 

 

 

 

 

 

 

 

 

Bytes

Cycles

Opcode

 

 

 

 

 

 

(Hex)

 

 

opc

 

1

4

8F

Example:

Given: SYM = 01H:

 

 

 

 

DI

 

 

 

If the value of the SYM register is 01H, the statement "DI" leaves the new value 00H in the register and clears SYM.0 to "0", disabling interrupt processing.

Before changing IMR, interrupt pending and interrupt source control register, be sure DI state.

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Page 165
Image 165
Samsung S3F80JB manual DI Disable Interrupts, Operation SYM 0 ←, No flags are affected