Avago Technologies LSI8751D - Manual (Page 116)

4-24 Signal Descriptions
•
MAD[0] Slow ROM pin. When pulled down, it enables two extra
clock cycles of data access time to allow use of slower memory
devices.
Note: All MAD pins have internal pull-up resistors.
Table 4.15 External Memory Support
MAD[3:1] Available Memory Space
000 16 Kbytes
001 32 Kbytes
010 64 Kbytes
011 128 Kbytes
100 256 Kbytes
101 512 Kbytes
110 1024 Kbytes
111 No external memory present