
5.0 X-Bus Extension
(Continued)
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108
Revision1.2
P
5.4.2
This register affects the functionality mode of the X-Bus.
Power Well:V
SB
Location:Offset 00h
Type:
R/W or RO
X-Bus Configuration Register (XBCNF)
5.4.3
These registers control the mapping of I/O and Memory Zones to XCSn, where n is from 0 to 3.
Power Well:V
SB
Location:Offset 01h (XZCNF0)
Location:Offset 02h (XZCNF1)
Location:Offset 0Dh (XZCNF2)
Location:Offset 0Eh (XZCNF3)
Type:
R/W or RO
X-Bus Select Configuration Registers (XZCNF0 to XZCNF3)
Bit
7
6
5
4
3
2
1
0
Name
TBXCS3
TBXCS2
TBXCS1
TBXCS0
Reserved
LADEN
Reset
0
0
0
0
0
0
0
Strap
Bit
Description
7
TBXCS3 (Turbo Transactions on XCS3).
When set to 1 and mode 0 is selected (TRANSMD = 0 in the XZM3
register), enables Turbo X-Bus transactions (see Section 5.2.7 on page 99) when XCS3 is accessed. The Turbo
transactions are Normal Address or Latched Address (see Section 5.2.9 on page 101), according to the setting
of the LADEN bit. This bit is locked by setting at least one of the LOCKXSCF bits in the XZM0-XZM3 registers.
0: Disabled (default)
1: Enabled
6
TBXCS2 (Turbo Transactions on XCS2).
When set to 1 and mode 0 is selected (TRANSMD = 0 in the XZM2
register), enables Turbo X-Bus transactions (see Section 5.2.7 on page 99) when XCS2 is accessed. The Turbo
transactions are Normal Address or Latched Address (see Section 5.2.9 on page 101), according to the setting
of the LADEN bit. This bit is locked by setting at least one of the LOCKXSCF bits in the XZM0-XZM3 registers.
0: Disabled (default)
1: Enabled
5
TBXCS1 (Turbo Transactions on XCS1).
When set to 1 and mode 0 is selected (TRANSMD = 0 in the XZM1
register), enables Turbo X-Bus transactions (see Section 5.2.7 on page 99) when XCS1 is accessed. The Turbo
transactions are Normal Address or Latched Address (see Section 5.2.9 on page 101), according to the setting
of the LADEN bit. This bit is locked by setting at least one of the LOCKXSCF bits in the XZM0-XZM3 registers.
0: Disabled (default)
1: Enabled
4
TBXCS0 (Turbo Transactions on XCS0).
When set to 1 and mode 0 is selected (TRANSMD = 0 in the XZM0
register), enables Turbo X-Bus transactions (see Section 5.2.7 on page 99) when XCS0 is accessed. The Turbo
transactions are Normal Address or Latched Address (see Section 5.2.9 on page 101), according to the setting
of the LADEN bit. This bit is locked by setting at least one of the LOCKXSCF bits in the XZM0-XZM3 registers.
0: Disabled (default)
1: Enabled
3-1
Reserved.
0
LADEN (Latch Address Mode Enabled).
When set to 1, enables addresses XA27-XA4 to be multiplexed with
the data pins in three phases. Reset value of this bit is set according to the XCNF2 strap, sampled at V
SB
Power-Up reset. See Section 1.4.11 on page 29 for the definition of strap setting. This bit is locked by setting at
least one of the LOCKXSCF bits in the XZM0-XZM3 registers.
0: Disabled (default if XCNF2 = 0 - No BIOS)
1: Enabled (default if XCNF2 = 1 - With BIOS)