© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
User manual
Rev. 01 — 15 August 2005
47
Philips Semiconductors
UM10139
Volume 1
Chapter 4: MAM Module
[1]
Instruction prefetch is enabled in modes 1 and 2.
[2]
The MAM actually uses latched data if it is available, but mimics the timing of a Flash read operation. This
saves power while resulting in the same execution timing. The MAM can truly be turned off by setting the
fetch timing value in MAMTIM to one clock.
[1]
The MAM actually uses latched data if it is available, but mimics the timing of a Flash read operation. This
saves power while resulting in the same execution timing. The MAM can truly be turned off by setting the
fetch timing value in MAMTIM to one clock.
4.5 MAM configuration
After reset the MAM defaults to the disabled state. Software can turn memory access
acceleration on or off at any time. This allows most of an application to be run at the
highest possible performance, while certain functions can be run at a somewhat slower
but more predictable rate if more precise timing is required.
4.6 Register description
All registers, regardless of size, are on word address boundaries. Details of the registers
appear in the description of each function.
Table 30:
MAM Responses to program accesses of various types
Program Memory Request Type
MAM Mode
0
1
2
Sequential access, data in latches
Initiate Fetch
Use Latched
Data
Use Latched
Data
Sequential access, data not in latches
Initiate Fetch
Initiate Fetch
Initiate Fetch
Non-sequential access, data in latches
Initiate Fetch
Initiate Fetch
Use Latched
Data
Non-sequential access, data not in latches Initiate Fetch
Initiate Fetch
Initiate Fetch
Table 31:
MAM responses to data and DMA accesses of various types
Data Memory Request Type
MAM Mode
0
1
2
Sequential access, data in latches
Initiate Fetch
Initiate Fetch
Use Latched
Data
Sequential access, data not in latches
Initiate Fetch
Initiate Fetch
Initiate Fetch
Non-sequential access, data in latches
Initiate Fetch
Initiate Fetch
Use Latched
Data
Non-sequential access, data not in latches Initiate Fetch
Initiate Fetch
Initiate Fetch