
DSP1611/17/18/27/28/29 DIGITAL SIGNAL PROCESSOR
Information Manual
Serial I/O
April 1998
7-18
DRAFT COPY
Lucent Technologies Inc.
7.6 Multiprocessor Mode Description
(continued)
7.6.2 Detailed Multiprocessor Mode Description (continued)
shows the time slot allocation timing used when in multiprocessor mode. A high-to-low transition of
SYNC (SYN) defines the beginning of time slot 0 and resynchronizes any DSP devices that are operating on the
multiprocessor bus with SYN as an input. The DSP device that drives the multiprocessor bus during time slot 0
also drives the SYN line because of the way the tdms register is encoded. For this reason, one DSP device must
always drive during time slot 0 unless SYN is externally generated. Eight words are exchanged within each SYN
frame, so the tdms register should have the SYNCSP field set low if in multiprocessor mode. This provides 128
active ICK and/or OCK (CK) cycles per SYN frame (8 words
×
16 bits/word). The DATA and ADD lines allow the
serial transfer of 16 bits of data and 16 bits of address (eight destination and eight source bits) per time slot.
Although the ILD and OLD signals need not be connected to anything while in multiprocessor mode, they must
both be set in active mode and their behavior is shown in
. The ILD output clocks with every time slot to
read in each word of address and data and the OLD output clocks only on those time slots during which the DSP in
question actually drives the multiprocessor bus. In the example in
, OLD is shown assuming that the
DSP drives during time slots 0, 2, and 5. Multiprocessor mode is turned on by setting the tdms MODE field (bit 9)
to one.
5-4185
† OLD shown assuming DSP1611/17/18/27/28/29 drives bus in time slots 0, 2, and 5 (tdms = 0x125).
Figure 7-15. Multiprocessor Mode time slots
In multiprocessor mode, each device can send data in a unique time slot designated by the tdms register transmit
slot field (bits 7—0). The tdms register has fully decoded fields to allow one DSP device to transmit in more than
one time slot. This procedure is useful for multiprocessor systems with less than eight DSP devices if a higher
bandwidth is necessary between certain devices in that system. Each device also has a fully decoded transmitting
address specified by the srta register transmit address field (bits 7—0, see
). This is used to transmit
information regarding the destination(s) of the data. The fully decoded receive address specified by the srta regis-
ter receive address field (bits 15—8) determines which data is received.
TIME
SLOT
0
1
2
3
4
5
6
7
0
CK
SYN
ILD
OLD
†
DATA
ADD
D[0:15]
D[0:15]
D[0:15]
D[0:15]
D[0:15]
D[0:15]
D[0:15]
D[0:15]
D[0:15]
A[0:15]
A[0:15]
A[0:15]
A[0:15]
A[0:15]
A[0:15]
A[0:15]
A[0:15]
A[0:15]
Содержание DSP1611
Страница 18: ...Chapter 1 Introduction...
Страница 27: ...Chapter 2 Hardware Architecture...
Страница 52: ...Chapter 3 Software Architecture...
Страница 116: ...Chapter 4 Instruction Set...
Страница 154: ...Chapter 5 Core Architecture...
Страница 176: ...Chapter 6 External Memory Interface...
Страница 208: ...Chapter 7 Serial I O...
Страница 237: ...Chapter 8 Parallel I O DSP1617 Only...
Страница 261: ...Chapter 9 Parallel Host Interface PHIF DSP1611 18 27 28 29 Only...
Страница 275: ...Chapter 10 Bit I O Unit...
Страница 284: ...Chapter 11 JTAG Test Access Port...
Страница 306: ...Chapter 12 Timer...
Страница 313: ...Chapter 13 Bit Manipulation Unit...
Страница 325: ...Chapter 14 Error Correction Coprocessor DSP1618 28 Only...
Страница 350: ...Chapter 15 Interface Guide...
Страница 367: ...Appendix A Instruction Encoding...
Страница 379: ...Appendix B Instruction Set Summary...
Страница 381: ...aD extractz aS IM16 B 52 aD insert aS arM B 53 aD insert aS IM16 B 54 aD aS aaT B 55...
Страница 437: ...Index...