3-16
Falcon ECC Memory Controller Chip Set
3
ROM/Flash Interface
The Falcon pair provides the interface for two blocks of ROM/Flash. Each
block provides addressing and control for up to 16Mbytes of memory
using two 8-bit devices, or up to 64Mbytes using two 32-bit devices or one
64-bit device. Note that no error checking (ECC or Parity) is provided for
the ROM/Flash.
The ROM/Flash interface allows each block to be individually configured
by jumpers and/or by software as follows:
1. Access for each block is controlled by two software program- mable
control register bits. One bit is an overall enable. The other is a write
enable to be used in programming Flash devices. The overall enable
bits are always cleared at reset.
Each block also has a reset vector enable bit that controls whether it
is enabled at $FFF00000-$FFFFFFFF. This reset vector enable bit
is cleared or set at reset depending on external jumper configuration.
This allows the board designer to use external jumpers to
enable/disable Block A/B ROM/Flash as the source of reset vectors.
The write enable bit is cleared at reset for both blocks.
2. The base address for each block is software programmable. At reset,
Block A’s base address is $FF000000 and Block B’s base address is
$FF400000.
As noted above, in addition to appearing at the programmed base
address, the first 1Mbyte of Block A/B also appears at $FFF00000-
$FFFFFFFF if the reset vector enable bit is set.
3. The assumed size for each block is software programmable. It is
initialized to its smallest setting at reset.
4. The assumed device type for Block A/B is determined by an
external jumper at reset time. It also is available as a status bit and
cannot be changed by software.
When the device type status bit is cleared, the block’s ROM /Flash
is considered to be two 8-bit devices with one device connected to
each Falcon. In this mode, the following rules are enforced:
a. both devices must be the same,
Содержание MVME2700 Series
Страница 1: ...MVME2600 2700 Series Single Board Computer Programmer s Reference Guide V2600A PG2 ...
Страница 13: ...xiv ...
Страница 15: ...xvi ...
Страница 67: ...1 50 Board Description and Memory Maps 1 ...
Страница 70: ...Introduction 2 3 2 Four 31 bit tick timers Two 64 bit general purpose registers for cross processor messaging ...
Страница 151: ...2 84 Raven PCI Host Bridge Multi Processor Interrupt Controller Chip 2 ...
Страница 215: ...3 64 Falcon ECC Memory Controller Chip Set 3 ...
Страница 277: ...Glossary GL 14 G L O S S A R Y ...