5.3 Host Commands

(27) WRITE BUFFER (X’E8’)

The host system can overwrite the contents of the data buffer of the device with a desired data pattern by issuing this command. Upon receipt of this command, the device sets the BSY bit of the Status register. Then the device sets the DRQ bit of Status register and clears the BSY bit when the device is ready to receive the data. After that, 512 bytes of data is transferred from the host and the device writes the data to the buffer, then generates an interrupt.

At command issuance (I/O registers setting contents)

1F7H(CM)

1

1

1

0

1

0

0

0

 

 

 

 

 

 

 

 

 

1F6H(DH)

x

x

x

DV

xx

 

 

 

 

 

 

 

 

 

 

 

 

1F5H(CH)

xx

 

 

 

 

 

 

 

1F4H(CL)

xx

 

 

 

 

 

 

 

1F3H(SN)

xx

 

 

 

 

 

 

 

1F2H(SC)

xx

 

 

 

 

 

 

 

1F1H(FR)

xx

 

 

 

 

 

 

 

At command completion (I/O registers contents to be read)

1F7H(ST)

Status information

 

 

 

 

 

 

 

 

1F6H(DH)

x

x

x

DV

xx

1F5H(CH)

xx

 

 

 

 

1F4H(CL)

xx

 

 

 

 

1F3H(SN)

xx

 

 

 

 

1F2H(SC)

xx

 

 

 

 

1F1H(ER)

Error information

 

 

C141-E202-01EN

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Image 151
Fujitsu MHU2100AT manual Write Buffer X’E8’