ADSP-2173_15 Datasheet, PDF (32/52 Pages) Analog Devices – DSP Microcomputer

ADSP-2171/ADSP-2172/ADSP-2173
ADSP-2173 TIMING PARAMETERS
GENERAL NOTES
Use the exact timing information given. Do not attempt to de-
rive parameters from the addition or subtraction of others.
While addition or subtraction would yield meaningful results for
an individual device, the values given in this data sheet reflect
statistical variations and worst cases. Consequently, you cannot
meaningfully add up parameters to derive longer times.
TIMING NOTES
Switching characteristics specify how the processor changes its
signals. You have no control over this timing; it is dependent on
the internal design. Timing requirements apply to signals that
are controlled outside the processor, such as the data input for a
read operation.
Timing requirements guarantee that the processor operates cor-
rectly with another device. Switching characteristics tell you
what the device will do under a given circumstance. Also, use
the switching characteristics to ensure any timing requirement
of a device connected to the processor (such as memory) is
satisfied.
MEMORY REQUIREMENTS
This chart links common memory device specification names
and ADSP-2173 timing parameters for your convenience.
Parameter
Name
Function
Common
Memory Device
Specification Name
t_ASW
A0-A13, DMS, PMS
Address Setup to
Setup before WR Low
Write Start
t_AW
A0-A13, DMS, PMS
Setup Address Setup
before WR Deasserted
to Write End
t_WRA
A0-A13, DMS, PMS
Address Hold Time
Hold after WR Deasserted
t_DW
Data Setup before WR High Data Setup Time
t_DH
Data Hold after WR High Data Hold Time
t_RDD
RD Low to Data Valid
OE to Data Valid
t_AA
A0-A13, DMS, PMS,
Address Access Time
BMS to Data Valid
–32–
REV. A