© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
User manual
Rev. 01 — 15 August 2005
49
Philips Semiconductors
UM10139
Volume 1
Chapter 4: MAM Module
4.9 MAM usage notes
When changing MAM timing, the MAM must first be turned off by writing a zero to
MAMCR. A new value may then be written to MAMTIM. Finally, the MAM may be turned
on again by writing a value (1 or 2) corresponding to the desired operating mode to
MAMCR.
For system clock slower than 20 MHz, MAMTIM can be 001. For system clock between
20 MHz and 40 MHz, Flash access time is suggested to be 2 CCLKs, while in systems
with system clock faster than 40 MHz, 3 CCLKs are proposed.
110
6 - MAM fetch cycles are 6 CCLKs in duration
111
7 - MAM fetch cycles are 7 CCLKs in duration
Warning: These bits set the duration of MAM Flash fetch operations
as listed here. Improper setting of this value may result in incorrect
operation of the device.
7:3
-
-
Reserved, user software should not write ones to reserved
bits. The value read from a reserved bit is not defined.
NA
Table 34:
MAM Timing register (MAMTIM - address 0xE01F C004) bit description
Bit
Symbol
Value Description
Reset
value