[signal]

[I/O]

[Description]

IORDY

O

This signal is negated to extend the host transfer cycle of any host

 

 

register access (Read or Write) when the device is not ready to

 

 

respond to a data transfer request.

DDMARDY–

O

DDMARDY– is a flow control signal for Ultra DMA data out bursts.

 

 

This signal is asserted by the device to indicate to the host that the

 

 

device is ready to receive Ultra DMA data out bursts. The device may

 

 

negate DDMARDY– to pause an Ultra DMA data out burst.

DSTROBE

O

DSTROBE is the data in strobe signal from the device for an Ultra

 

 

DMA data in burst. Both the rising and falling edge of

 

 

DSTROBE latch the data from DATA 0-15 into the host. The

 

 

device may stop generating DSTROBE edges to pause an Ultra

 

 

DMA data in burst.

CSEL

I

This signal to configure the device as a master or a slave device.

 

 

When CSEL signal is grounded, the IDD is a master device.

 

 

When CSEL signal is open, the IDD is a slave device.

 

 

This signal is pulled up with 10 kΩ resistor.

DMACK–

I

The host system asserts this signal as a response that the host

 

 

system receive data or to indicate that data is valid.

DMARQ

O

This signal is used for DMA transfer between the host system and

 

 

the device. The device asserts this signal when the device

 

 

completes the preparation of DMA data transfer to the host system

 

 

(at reading) or from the host system (at writing).

 

 

The direction of data transfer is controlled by the IOR- and IOW-

 

 

signals. In other word, the device negates the DMARQ signal

 

 

after the host system asserts the DMACK– signal. When there is

 

 

another data to be transferred, the device asserts the DMARQ

 

 

signal again.

 

 

When the DMA data transfer is performed, IOCW16–, CS0– and

 

 

CS1- signals are not asserted. The DMA data transfer is a 16-bit

 

 

data transfer. The device has a 10 kΩ pull-down resistor on this

 

 

signal.

GND

Grounded

Note:

"I" indicates input signal from the host to the device. "O" indicates output signal from the device to the host.

"I/O" indicates common output or bi-directional signal between the host and the device.

C141-E069-02EN

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Fujitsu MPD3XXXAT manual Iordy, Ddmardy