Cirrus-logic EP73xx Manual de usuario Pagina 88

  • Descarga
  • Añadir a mis manuales
  • Imprimir
  • Pagina
    / 158
  • Tabla de contenidos
  • MARCADORES
  • Valorado. / 5. Basado en revisión del cliente
Vista de pagina 87
8-4 EP7309/11/12 Users Manual - DS508UM4
Copyright Cirrus Logic, Inc. 2003
SRAM/Expansion Bus Controller
8
Wait States Field[2:5]:There aretwotablestouse to program achip selectwith
a specific number of wait states. One table is specifically for 13
and18 MHzoperation and the other isfor36 MHz and above. The
operating speed of the bus will determine which table is used.
01 32-bit wide bus access High, Low
10 Reserved High, Low
11 8-bit wide bus access High, Low
Table 8-3: Wait States at 13 / 18 MHz Operation
13 MHz / 18 MHz Operation
Bit 3 Bit 2 Bit 1 Bit 0 Wait States Random Wait States Sequential
xx00 4 3
xx01 3 2
xx10 2 1
xx11 1 0
Table 8-4: Wait States at 36 MHz Operation
36 MHz Operation
Bit 3 Bit 2 Bit 1 Bit 0 Wait States Random Wait States Sequential
0000 8 3
0001 7 3
0010 6 3
0011 5 3
0100 4 2
0101 3 2
0110 2 2
0111 1 2
1000 8 1
1001 7 1
1010 6 1
1011 5 1
1100 4 0
1101 3 0
1110 2 0
1111 1 0
Table 8-2: Bus Width Selection Settings
Bus Width Field Expansion Transfer Mode
Port E bits 1,0 during
nPOR reset
Vista de pagina 87
1 2 ... 83 84 85 86 87 88 89 90 91 92 93 ... 157 158

Comentarios a estos manuales

Sin comentarios