Missing bits in user manual LPC UM10503 ?

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Missing bits in user manual LPC UM10503 ?

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by marcinj on Fri Jan 17 04:18:28 MST 2014
There are some missing descriptions of bits in registers:
MAC_CONFIG -> bit on position 10
DMA_OP_MODE -> bits on positon 26, 25, 21

but in header file LPC43xx.h we have  for example:
#define ETHERNET_MAC_CONFIG_IPC_Pos                           10  

Where is an error?
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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by suckfish on Fri Jan 17 17:53:00 MST 2014
Hi,

Those bits are documented as 'Reserved' and value 0.  Which means don't use them, always write as zero when you set other bits at the same address.

The actual hardware implementation of a 'reserved' bit might be any of:

* unused;

* for testing only;

* an unsupported function that is present but not working in the hardware;

* intended for a function that is not actually implemented in this particular device;

* a magic supa-dupa thingy that they only want people buying more expensive devices to use;

Incidently, peripherals on ARM processors are often designed by ARM also. You may or may not find further documentation about the peripheral on ARMs website.
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