Motorola MVME2300 Series 用户手册
ISA Local Resource Bus
http://www.motorola.com/computer/literature
1-43
1
VME Geographical Address Register (VGAR)
The VME Geographical Address register is an 8-bit read-only register
located at ISA I/O address x1006. This register reflects the states of the
geographical address pins at the P1 connector.
located at ISA I/O address x1006. This register reflects the states of the
geographical address pins at the P1 connector.
Emulated Z8536 CIO Registers and Port Pins
Although MVME2300 series boards do not use a Z8536 device, several of
its functions are emulated within an ISA Register PLD. These functions
are accessed by reading/writing the Port A, B, C Data registers and Control
register. Note that the Pseudo IACK function is not implemented in the
MVME2300 series.
its functions are emulated within an ISA Register PLD. These functions
are accessed by reading/writing the Port A, B, C Data registers and Control
register. Note that the Pseudo IACK function is not implemented in the
MVME2300 series.
Emulated Z8536 Registers
The MVME2300 series implements the Z8536 CIO functions according to
the following table.
the following table.
REG
VME Geographical Address Register - Offset $1006
BIT
SD7
SD6
SD5
SD4
SD3
SD2
SD1
SD0
FIELD
GAP#
GA4#
GA3#
GA2#
GA1#
GA0#
OPER
READ ONLY
RESET
X
X
X
X
X
X
X
X
Table 1-20. Emulated Z8536 Access Registers
PCI I/O Address
Function
0000 0844
Port C’s Data Register
0000 0845
Port B’s Data Register
0000 0846
Port A’s Data Register
0000 0847
Control Register