Problems with communication between C167 and LM629N

Hi all,

i'm a student from germany. I got a problem with the addressing of an external bussystem. My C167 controls six LM629N (Precision Motion Controller IC) for an robot. A SN74LS138 Demux selects the LM629N. The Connections are:

SN74LS138 : C167
/E1 : /CS4
A2 : A3
A1 : A2
A0 : A1

LM629N : C167
D0..D7 : D0..D7
/WR : /WRL
/RD : /RD-U
/PS : A0

SN74LS138 : LM629
/O0../O5 : /CS

My concrete Questions:
1) How to setup the options for memoryspace with addrsel4/buscon4?
2) Wich Memorymodel should i use?
3) How can i read and write data to the LM639N.

I did tones of tries with all possible options,memory-models, near far and huge declarations for pointer, addrsel/buscon settings, dpp configuration .... (for example:

#define BASIS_ADRESSE 0x50000
unsigned char readLM629(unsigned char Achse)
{
 near unsigned char *pointer;
 pointer = ((near unsigned char*)(Achse*2 | BASIS_ADRESSE));
 return *pointer ;
}