ds96-039wdsp ETC-unknow, ds96-039wdsp Datasheet - Page 10

• Manufacturer Part Number: ds96-039wdsp
• Description: Clarification Serial Control Register Description Dsp1620/27/28/29 Devices
• Manufacturer: ETC-unknow

DSP1628 Digital Signal Processor
4 Hardware Architecture
The DSP1628 device is a 16-bit, fixed-point program-
mable digital signal processor (DSP). The DSP1628
consists of a DSP1600 core together with on-chip mem-
ory and peripherals. Added architectural features give
the DSP1628 high program efficiency for signal coding
applications.
4.1 DSP1628 Architectural Overview
Figure 4 shows a block diagram of the DSP1628. The
following modules make up the DSP1628.
DSP1600 Core
The DSP1600 core is the heart of the DSP1628 chip.
The core contains data and address arithmetic units,
and control for on-chip memory and peripherals. The
core provides support for external memory wait-states
and on-chip dual-port RAM and features vectored inter-
rupts and a trap mechanism.
Dual-Port RAM (DPRAM)
The DSP1628x16 contains 16 banks of zero wait-state
memory and the DSP1628x08 contains 8 banks of zero
wait-state memory. Each bank consists of 1K 16-bit
words and has separate address and data ports to the
instruction/coefficient and data memory spaces. A pro-
gram can reference memory from either space. The
DSP1600 core automatically performs the required mul-
tiplexing. If references to both ports of a single bank are
made simultaneously, the DSP1600 core automatically
inserts a wait-state and performs the data port access
first, followed by the instruction/coefficient port access.
A program can be downloaded from slow, off-chip mem-
ory into DPRAM, and then executed without wait-states.
DPRAM is also useful for improving convolution perfor-
mance in cases where the coefficients are adaptive.
Since DPRAM can be downloaded through the JTAG
port, full-speed remote in-circuit emulation is possible.
DPRAM can also be used for downloading self-test
code via the JTAG port.
8
Read-Only Memory (ROM)
The DSP1628 contains 48K 16-bit words of zero wait-
state mask-programmable ROM for program and fixed
coefficients.
External Memory Multiplexer (EMUX)
The EMUX is used to connect the DSP1628 to external
memory and I/O devices. It supports read/write opera-
tions from/to instruction/coefficient memory (X memory
space) and data memory (Y memory space). The
DSP1600 core automatically controls the EMUX. In-
structions can transparently reference external memory
from either set of internal buses. A sequencer allows a
single instruction to access both the X and the Y exter-
nal memory spaces.
Clock Synthesis
The DSP powers up with a 1X input clock (CKI/CKI2) as
the source for the processor clock. An on-chip clock
synthesizer (PLL) can also be used to generate the sys-
tem clock for the DSP, which will run at a frequency mul-
tiple of the input clock. The clock synthesizer is
deselected and powered down on reset. For low-power
operation, an internally generated slow clock can be
used to drive the DSP. If both the clock synthesizer and
the internally generated slow clock are selected, the
slow clock will drive the DSP; however, the synthesizer
will continue to run.
The clock synthesizer and other programmable clock
sources are discussed in Section 4.13. The use of these
programmable clock sources for power management is
discussed in Section 4.14.
Lucent Technologies Inc.
February 1997