Samsung spinpoint v40 Manuale Utente

DISK DRIVE OPERATION 

 

SpinPoint V40 Product Manual

89

 

 
The minimum cycle time supported by the device in PIO mode 3, 4 and Multiword DMA mode 1, 2 
respectively, shall always be greater than, or equal to the minimum cycle time defined by the associated 
mode. For example, a device supporting PIO mode 4 timing shall not report a value less than 120ns, the 
minimum cycle time defined for PIO mode 4 timings.  
 
 

 
Figure 6-1 defines the relationships between the interface signals for register transfers.  Peripherals reporting 
support for PIO mode 3 or 4 shall power up in a PIO mode 0, 1, or 2. 
 
For PIO modes 3 and above, the minimum value of t

0

 is specified by word 68 in the IDENTIFY DEVICE 

parameter list.  Table 6-16 defines the minimum value that shall be placed in word 68. 
 
IORDY will be supported when PIO modes 3 or 4 are the current mode of operation.  
 

NOTE 

−

 Some devices implementing the PACKET Command feature set prior to this 

standard power up in PIO mode 3 and enable IORDY as the default.