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8 flash control/status register, Table 6-7, Flash control/status register – Artesyn MVME3100 Single Board Computer Installation and Use (June 2014) User Manual

Page 112

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Memory Maps

MVME3100 Single Board Computer Installation and Use (6806800M28E)

112

6.1.8

Flash Control/Status Register

The MVME3100 provides software-controlled bank write protect and map select functions as
well as boot block select, bank write protect, and activity status for the Flash.

FLASH_RDY: Flash ready. This bit provides the current state of the Flash devices’ Ready/Busy#
pins. These open drain output pins from each Flash device are wire OR'd to form Flash Ready.

FBT_BLK_SEL: Flash boot block select. This bit reflects the current state of the BOOT BLOCK B
SELECT switch. A cleared condition indicates that boot block A is selected and mapped to the
highest address. A set condition indicates that boot block B is selected and mapped to the
highest address.

F_WP_HW: Hardware Flash bank write protect switch status. This bit reflects the current state
of the FLASH BANK WP switch. A set condition indicates that the entire Flash bank is write
protected. A cleared condition indicates that the Flash bank is not write protected.

F_WP_SW: Software Flash bank write protect. This bit provides software-controlled
protection against inadvertent writes to the Flash memory devices. A set condition indicates
that the entire Flash is write-protected. A cleared condition indicates that the Flash bank is not
write-protected, only when the hardware write-protect bit is also not set. This bit is set during
reset and must be cleared by the system software to enable writing of the Flash devices.

MAP_SEL: Memory map select. When this bit is cleared, the Flash memory map is controlled
by the Flash Boot Block Select switch. When the map select bit is set, boot block A is selected
and mapped to the highest address.

Table 6-7 Flash Control/Status Register

REG

Flash Control/Status Register - 0xE2000003

BIT

7

6

5

4

3

2

1

0

FIELD

RS

V

D

RS

V

D

RS

V

D

MAP_SEL

F_WP_SW

F_WP_HW

FB

T_BLK_SEL

FLA

SH_RD

Y

OPER

R

R

R

R/W

R/W

R

R

R

RESET

0

0

0

0

1

X

X

1