Local-bus-to-vmebus i/o control register, Local-bus-to-vmebus i/o control register -50 – Motorola MVME1X7P User Manual

Page 140

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2-50

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VMEchip2

2

Local-Bus-to-VMEbus I/O Control Register

This register controls the VMEbus short I/O map and the F page
($F0000000 through $FF7FFFFF) I/O map.

I1SU

When this bit is high, the VMEchip2 drives a supervisor
address modifier code when the short I/O space is
accessed. When this bit is low, the VMEchip2 drives a
user address modifier code when the short I/O space is
accessed.

I1WP

When this bit is high, write posting is enabled to the
VMEbus short I/O segment. When this bit is low, write
posting is disabled to the VMEbus short I/O segment.

I1D16

When this bit is high, D16 data transfers are performed to
the VMEbus short I/O segment. When this bit is low, D32
data transfers are performed to the VMEbus short I/O
segment.

I1EN

When this bit is high, the VMEbus short I/O map decoder
is enabled. When this bit is low, the VMEbus short I/O
map decoder is disabled.

I2PD

When this bit is high, the VMEchip2 drives a program
address modifier code when the F page is accessed. When
this bit is low, the VMEchip2 drives a data address
modifier code when the F page is accessed.

I2SU

When this bit is high, the VMEchip2 drives a supervisor
address modifier code when the F page is accessed. When
this bit is low, the VMEchip2 drives a user address
modifier code when the F page is accessed.

ADR/SIZ

$FFF4002C (8 bits of 32)

BIT

15

14

13

12

11

10

9

8

NAME

I2EN

I2WP

I2SU

I2PD

I1EN

I1D16

I1WP

I1SU

OPER

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

RESET

0 PSL

0 PS

O PS

0 PS

0 PS

O PS

0 PS

O PS

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