pnx1700 NXP Semiconductors, pnx1700 Datasheet - Page 478

• Manufacturer Part Number: pnx1700
• Description: Connected Media Processor
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Volume 1 of 1
PNX17XX_SER_1
Preliminary data sheet
Figure 6:
fgpo_start
fgpo_stop
fgpo_data
clk_fgpo
Back-to-back Message Passing Example
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3.2 Message Passing Mode
3.3 PNX1300 Series Message Passing Mode
3.4 Record Output Mode
If FGPO_REC_SIZE is not a multiple of 4 bytes, the message will be read from main
memory as a series of 32-bit words. Only the last word is partially used.
Message start is signaled on the fgpo_start pin and message stop is signaled on the
fgpo_stop pin. See FGPO_CTL.MSG_START and FGPO_CTL.MSG_STOP for
selecting which edge will be active.
Figure 6
start event is set to the falling edge of fgpo_start and the message stop event is set to
the rising edge of fgpo_stop.
Message mode requires both fgpo_start and fgpo_stop signals to operate. External
buffer sync is not used with message mode. Buffers are switched when the number of
messages sent equals the value programmed into the FGPO_SIZE register.
THE MINIMUM MESSAGE SIZE is 2. FGPO_REC_SIZE must be programmed
greater than 1.
If the outgoing message length is greater than the value programmed into the
FGPO_REC_SIZE register, the message is truncated.
PNX1300 Series Message Passing mode can be emulated by setting FGPO_SIZE to
1 and only enabling buffer 1 (FGPO_CTL.OUTPUT_ENABLE_1 = ‘1’).
If FGPO_REC_SIZE is not a multiple of 4 bytes, the record will be read from main
memory as a series of 32-bit words. Only the last word is partially used.
Record start is signaled on the fgpo_start (fgpo_rec_start) pin. See
FGPO_CTL.MSG_START (REC_SYNC) for selecting which edge will be active.
Buffer switching is signaled on the fgpo_stop (fgpo_buf_start) pin. See
FGPO_CTL.MSG_STOP (BUF_SYNC) for selecting which buffer sync method will be
used.
D1
illustrates an example of a two 8-sample message transfer. The message
D2
Rev. 1 — 17 March 2006
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D4
Chapter 13: FGPO: Fast General Purpose Output
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D6
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
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PNX17xx Series
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