Technical data

Configuration Switch (S4) Hardware Preparation and Installation
MVME3100 Single Board Computer Installation and Use (6806800G36A)
21
1.4.2 Configuration Switch (S4)
An 8-position SMT configuration switch controls the VME SCON setting, Flash bank write-
protect, and the safe start ENV settings. It also selects the Flash boot image. The default setting
on all switch positions is OFF.
Table 1-2 Configuration Switch (S4) Settings
Switch Pos.
Setting
NotesOFF (Factory Default) ON
SAFE_START 1 Normal ENV settings
should be used.
Safe ENV settings
should be used.
This switch status is
readable from
System Status
register 1, bit 5.
Software may check
this bit and act
accordingly.
BOOT BLOCK
SELECT
2 Flash memory map is
normal and boot block A
is selected.
Boot block B is
selected and
mapped to the
highest address.
FLASH BANK WP 3 Entire Flash is not write-
protected.
Flash is write-
protected.
Reserved 4
VME SCON
AUTO/MANUAL
MODE
5 Auto-SCON mode. Manual SCON mode. Manual SCON mode
works in conjunction
with the VME SCON
SELECT switch.
MANUAL VME
SCON SELECT
6 Non-SCON mode. Always SCON mode. This switch is only
effective when the
VME SCON
AUTO/MANUAL
MODE switch is ON.
sATA Mode 7 Legacy Mode sATA Mode Sets GD31244 to
legacy or sATA mode
during reset
TRST SELECT 8 Normal MPC8540 TRST
mode where the board
HRESET will assert
TRST.
Isolates the board
HRESET from TRST
and allows the board
to reset without
resetting the
MPC8540
JTAG/COP interface.
This switch should
remain in the OFF
position unless a
MPC8540 emulator is
attached.