pnx1700 NXP Semiconductors, pnx1700 Datasheet - Page 783

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

Philips Semiconductors
Volume 1 of 1
1.
PNX17XX_SER_1
Preliminary data sheet
All references to “Set A” registers also apply equally to “Set B”.
The combination of these three basic algorithms operate together in the arbiter as
shown in
The TDMA timing wheel is implemented with 128 entries, numbered 1 to 128. The
TDMA_entries field in the NR_entries_A
entries that are used. TDMA entries higher than this value will be ignored. If the
TDMA_entries is greater than 128 then all 128 entries are used, but no more. If
TDMA_entries is set to zero then the TDMA timing wheel is not used for arbitration.
The priority list is implemented with 16 entries, numbered 1 to 16. The
Priority_entries field in the NR_entries_A register will determine the actual number of
entries that are used. If a value greater than 16 is written all 16 entries are used, but
no more. If the Priority_entries is set to zero then the priority list is not used for
arbitration.
The round robin #1 list is implemented with 16 entries, numbered 1 to 16. The
round_robin1_entries
number of entries that are used. If a value greater than 16 is written all 16 entries are
used, but no more. If the
is not used for arbitration.
The round robin #2 list is implemented with 8 entries, numbered 1 to 8. The
round_robin2_entries
number of entries that are used. If a value greater than 8 is written all 8 entries are
used, but no more. If the
is not used for arbitration.
Figure 1:
Figure
Arbitration Scheme
1.
Rev. 1 — 17 March 2006
field in the NR_entries_A register will determine the actual
field in the NR_entries_A register will determine the actual
Timing Wheel
round_robin1_entries
round_robin2_entries
TDMA
high
low
round robin #1
round robin #2
priority list
1
register will determine the actual number of
is set to zero then the round robin #1 list
is set to zero then the round robin #2 list
highest
lowest
overall priority
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
Chapter 26: Memory Arbiter
PNX17xx Series
26-4