Memory Controller

6.8.5Expansion Card Interface Timing Diagrams and Parameters

Figure 6-29shows a 16-bit access to a 16-bit memory or I/O device. When common memory is accessed, the MCMEM0 and MCMEM1 registers are used, depending on whether card socket 0 or 1 is addressed. MCIO0 and MCIO1 are used for I/O accesses and MCATT0 and MCATT1 are used for access to attribute memory.

Figure 6-29. 16-Bit PC Card Memory or I/O 16-Bit (Half-word) Access

0ns

MEMCLK

MA,nPREG,PSKTSEL

nPCE2,nPCE1

x_SET

nPWE,nPOE,nPIOW,nPIOR RDnWR

nIOIS16

nPWAIT read_data write_data

50ns

100ns

 

 

 

 

 

 

 

x_HOLD

x_ASST_HOLD

x_ASST_WAIT + wait states

150ns

Intel® PXA255 Processor Developer’s Manual

6-69

Page 251
Image 251
Intel PXA255 Expansion Card Interface Timing Diagrams and Parameters, Bit PC Card Memory or I/O 16-Bit Half-word Access