Analog Devices ADSP-21992 EZ-KIT LITE, Системное руководство

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ADSP-21992 EZ-KIT Lite Evaluation System Manual 3-7
EZ-KIT Lite Hardware Reference
External Memory Interface (EMI)
A 64K x 16-bit SRAM IC (
U8
) is provided on the External Memory Inter-
face (EMI) of the ADSP-21992 EZ-KIT Lite board.
Sockets are provided on the ADSP-21992 EZ-KIT Lite board so that the
EMI can also be connected to two 512K x 8-bit flash memory ICs (
U5
and
U6
). These Flash memory ICs are connected to the boot memory select pin
(
BMS
) and the memory select 0 pin (
MS0
), allowing the Flash memory to
boot the DSP as well as store information during normal operation.
8-bit-wide (and 16-bit, if implemented in boot ROM) booting is possible.
Refer to
“Memory Map” on page 2-3 for information about the location
of the flash memory in the DSP’s memory map.
Jumpers are provided to allow mapping RAM into different banks. A
two-nput AND gate with a jumper allows mapping the Flash memory into
boot memory space or
MS0
.
All address, data, and control signals are available externally on a connec-
tor. The pin-out of the EMI connector (
P3
) can be found in the
schematics in the Appendix.
SPI Interface
The SPI signals (
MISO
,
MOSI
, and
SCK
) are available on connector
P7
.
SPI EEPROM
A socket for an 8-pin SPI Serial EEPROM (64K x 8-bit), such as the
Microchip 25LC640, is provided on the ADSP-21992 EZ-KIT Lite
board, for booting and/or data storage. The
PF1
/
SPISEL1
pin of the
ADSP-21992 is used to select the SPI Serial EEPROM to be active on the
SPI interface. Jumper
JP14
is used to disable the EEPROM when the
PF1
/
SPISEL1
pin of the ADSP-21992 is being used as a programmable flag pin.