Lpc2000

We recently discovered a bug in the MAM block and it affects the  
LPC213x family, description of which is provided below. The Errata 
sheet (for this family) has been updated and is on its way for 
publishing. 

--------------------------------------------------------------------
MAM.1		
Incorrect read of data from SRAM while code is running from Flash and 
MAM is disabled

Introduction:
The Memory Accelerator Module (MAM) provides nearly zero-wait state 
execution from the on-chip flash at higher frequencies.

Problem:
While code is running from the on-chip Flash, if a data fetch is 
initiated from SRAM, the data read might be corrupted.

Work-around:		
There are two possible workarounds: 
1. Fully enable the MAM (MAMCR=0x2) and use the appropriate MAMTIM 
value. Enabling the MAM will reduce current consumption (since the 
MAM buffers four ARM or eight Thumb instructions with each Flash 
fetch) and also provide nearly zero-wait state execution from Flash 
above 20MHz.
2. Disable MAM (MAMCR=0x0) and set MAMTIM=0x1. If the MAM is 
disabled, this will lead to increased current consumption as each 
fetch will result in a read of the Flash memory. In addition, it 
limits execution out of Flash to 20MHz. This approach would however 
provide deterministic behaviour.

The first workaround is the recommended solution as the application 
can achieve considerable power savings and also does not put any 
restriction on the operating frequency.	

---------------------------------------------------------------------


Best Regards,
Philips Apps