CHAPTER 3 REGISTERS

Table 3.4-1 Conversion Rule for Actual Address of Direct Addressing and Bit

Direct Addressing

Operand address

Direct bank pointer (DP)

Actual address

 

 

 

00H to 7FH

 

0000H to 007FH

 

 

 

 

000

0080H to 00FFH

 

 

 

 

001

0100H to 017FH

 

 

 

 

010

0180H to 01FFH

 

 

 

80H to FFH

011

0200H to 027FH

 

 

100

0280H to 02FFH

 

 

 

 

 

101

0300H to 037FH

 

 

 

 

110

0380H to 03FFH

 

 

 

 

111

0400H to 047FH

 

 

 

Program Status (PS) Flags

The program status flags are explained below.

H flag

This flag is 1 if a carry from bit 3 to bit 4 or a borrow from bit 4 to bit 3 is generated as the result of an operation, and it is 0 in other cases. Because it is used for decimal compensation instructions, it cannot be guaranteed if it is used for applications other than addition or subtraction.

I flag

An interrupt is enabled when this flag is 1 and is disabled when it is 0. It is set to 0 at reset which results in the interrupt disabled state.

IL1, IL0

These bits indicate the level of the currently-enabled interrupt. The interrupt is processed only when an interrupt request with a value less than that indicated by these bits is issued.

IL1

IL0

Interrupt level

High and low

 

 

 

 

 

0

0

0

Highest

 

 

 

 

 

0

1

1

 

 

 

 

 

 

 

 

 

1

0

2

 

 

 

 

 

Lowest

1

1

3

 

 

 

 

 

N flag

This flag is 1 when the most significant bit is 1 and is 0 when it is 0 as the result of an operation.

Z flag

This flag is 1 when the most significant bit is 0 and is 0 in other cases as the result of an operation.

V flag

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Fujitsu F2MC-8FX manual Program Status PS Flags, IL1 IL0