LPC1317 usart register, 2 diff regsiters having same address

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by aamir ali on Wed Aug 28 03:16:57 MST 2013
In usart how can 2 different registers share same address.

1.  RBR,THR,DLL share same address. RBR & THR can be same like as they are buffer register but DLL has different functin. How can it share address. Or it the function of DLAB bit which make changes ion hardware register on when a regsiter will be accessed.
So if DLAB = 0 & read then RBR
if DLAB = 0 & write then THR
if DLAB = 1 & r/w then DLL.

2. Or same goes for ( DLM & IER ) & ( IIR & FCR ).