2 end-of-interrupt register, Figure 817. interrupt vector register (slave mode – Intel 80C188XL User Manual
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INTERRUPT CONTROL UNIT
Figure 8-17. Interrupt Vector Register (Slave Mode Only)
8.5.1.2
End-Of-Interrupt Register
The End-of-Interrupt (EOI) register has the same function in Slave mode as in Master mode.
However, non-specific EOI commands are not supported, so the NSPEC bit is omitted from the
register. Only specific EOI commands can be issued. To clear an In-Service bit in Slave mode,
write the three least-significant bits of the interrupt type (from Table 8-5) to the VT2:0 bits.
Register Name:
Interrupt Vector Register (Slave Mode only)
Register Mnemonic:
INTVEC
Register Function:
Specifies the five most-significant bit of the interrupt
vector types for the internal interrupt sources
Bit
Mnemonic
Bit Name
Reset
State
Function
T4:0
Interrupt
Vector Type
Field
00000
Specifies the five most-significant bits of the
interrupt vector types for the internal interrupt
sources. The three least-significant bits are
fixed (see Table 8-5).
NOTE:
Reserved register bits are shown with gray shading. Reserved bits must be written
to a logic zero to ensure compatibility with future Intel products.
A1196-A0
15
0
T
0
T
2
T
1
T
3
T
4