Computer Hardware User Manual

Table Of Contents
Programming Model
http://www.motorola.com/computer/literature 4-15
4
Base Address Register
These eight bits are combined with the two most significant bits in Register
7 (the next register) to form BAD31-BAD22, which defines the base
address of the memory. For larger memory sizes, the lower significant bits
are ignored.
The bit assignments for the Base Address register are:
DRAM Control Register
The bit assignments for the DRAM Control register are:
RAMEN RAM Enable. This control bit is used to enable the local
bus to perform read/write accesses to the memory.
Accesses are enabled when this bit is set and are disabled
when this bit is cleared. This bit should only be set after
BAD31-BAD22 have been initialized.
ADR/SIZ 1st $FFF43014/2nd $FFF43114 (8-bits)
BIT 31 30 29 28 27 26 25 24
NAME BAD31 BAD30 BAD29 BAD28 BAD27 BAD26 BAD25 BAD24
OPER R/W R/W R/W R/W R/W R/W R/W R/W
RESET 0 PLS0 PLS0 PLS0 PLS0 PLS0 PLS0 PLS0 PLS
ADR/SIZ 1st $FFF43018/2nd $FFF43118 (8-bits)
BIT 31 30 29 28 27 26 25 24
NAME BAD23 BAD22 RWB5 RWB4 RWB3 NCEIEN NCEBEN RAMEN
OPER R/W R/W R/W R/W R/W R/W R R/W
RESET 0 PLS 0 PLS 0 PLS 0 PLS 0 PLS 0 PLS 0 PLS 0 PLS