5.5 Ultra DMA Feature Set

8)The device may assert DSTROBE tZIORDY after the host has asserted DMACK-

. Once the device has driven DSTROBE the device shall not release DSTROBE until after the host has negated DMACK- at the end of an Ultra DMA burst.

9)The host shall negate STOP and assert HDMARDY- within tENV after asserting DMACK-. After negating STOP and asserting HDMARDY-, the host shall not change the state of either signal until after receiving the first transition of DSTROBE from the device (i.e., after the first data word has been received).

10)The device shall drive DD (15:0) no sooner than tZAD after the host has asserted DMACK-, negated STOP, and asserted HDMARDY-.

11)The device shall drive the first word of the data transfer onto DD (15:0). This step may occur when the device first drives DD (15:0) in step (10).

12)To transfer the first word of data the device shall negate DSTROBE within tFS after the host has negated STOP and asserted HDMARDY-. The device shall negate DSTROBE no sooner than tDVS after driving the first word of data onto DD (15:0).

5.5.3.2 The data in transfer

The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.3.3 and 5.6.3.2 for specific timing requirements):

1)The device shall drive a data word onto DD (15:0).

2)The device shall generate a DSTROBE edge to latch the new word no sooner than tDVS after changing the state of DD (15:0). The device shall generate a DSTROBE edge no more frequently than tCYC for the selected Ultra DMA Mode. The device shall not generate two rising or two falling DSTROBE edges more frequently than 2tCYC for the selected Ultra DMA mode.

3)The device shall not change the state of DD (15:0) until at least tDVH after generating a DSTROBE edge to latch the data.

4)The device shall repeat steps (1), (2) and (3) until the data transfer is complete or an Ultra DMA burst is paused, whichever occurs first.

5.5.3.3Pausing an Ultra DMA data in burst

The following steps shall occur in the order they are listed unless otherwise specifically allowed (see 5.6.3.4 and 5.6.3.2 for specific timing requirements).

a)Device pausing an Ultra DMA data in burst

1)The device shall not pause an Ultra DMA burst until at least one data word of an Ultra DMA burst has been transferred.

2)The device shall pause an Ultra DMA burst by not generating DSTROBE edges.

NOTE - The host shall not immediately assert STOP to initiate Ultra DMA burst termination when the device stops generating

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Fujitsu MHW2040AC, MHW2060AC manual Data in transfer, Pausing an Ultra DMA data in burst

MHW2060AC, MHW2040AC specifications

The Fujitsu MHW2040AC and MHW2060AC are notable hard disk drives (HDDs) that have been widely used in various computing applications, especially in laptops and compact devices. These models are part of Fujitsu's commitment to providing reliable storage solutions that meet the demands of modern computing.

The MHW2040AC offers a storage capacity of 40 GB, while the MHW2060AC provides a slightly larger capacity at 60 GB. This range of storage makes both models suitable for users looking for dependable space for documents, multimedia files, and software applications. Both drives utilize a 2.5-inch form factor, ideal for mobile computing, as they are lightweight and designed to fit into space-constrained environments.

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In summary, the Fujitsu MHW2040AC and MHW2060AC are reliable, efficient, and user-friendly hard disk drives that combine moderate capacities with advanced features designed to enhance performance, ensure data integrity, and extend device longevity. These drives are well-suited for a range of applications, making them a solid choice for users seeking dependable storage solutions.