DSP56800FMD MOTOROLA [Motorola, Inc], DSP56800FMD Datasheet - Page 28

• Manufacturer Part Number: DSP56800FMD
• Description: Preliminary Technical Data DSP56F826 16-bit Digital Signal Processor
• Manufacturer: MOTOROLA [Motorola, Inc]

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Note: During read-modify-write instructions and internal instructions, the address lines do not change state.
(See Note)
A0–A15,
D0–D15
1.
T = Clock Period. For 80MHz operation, T = 12.5ns.
2.
To calculate the required access time for an external memory for any frequency < 80Mhz, use this formula:
Top = Clock period @ desired operating frequency
WS = Number of wait states
Memory Access Time = (Top*WS) + (Top- 11.5)
PS, DS
Timing is both wait state and frequency dependent. In the formulas listed, WS = the number of wait states and
Parameters listed are guaranteed by design.
WR
RD
t
AWR
t
WRWR
Figure 12. External Bus Asynchronous Timing
t
WRD
t
DOS
DSP56F826 Preliminary Technical Data
t
WR
Data Out
t
ARDA
t
WRRD
t
DOH
t
AD
t
ARDD
t
RD
Data In
t
RDD
t
t
RDRD
RDWR
t
t
DRD
RDA