SMSC USB2640i Manual De Usuario

Ultra Fast USB 2.0 Multi-Format Flash Media Controller/USB Hub Combo

Revision 2.0 (10-03-08)

18

SMSC USB2640/USB2641

xD Write Enable

xD_nWE

22

O12PU

This pin is an active low write strobe signal for the 

xD device. 

When using the internal FET, this pin has an 

internal weak pull-up resistor that is tied to the 

output of the internal Power FET, and is controlled 

by the xD_PU bit of the xDC_CTL register.

If an external FET is used (Internal FET is 

disabled), then the internal pull-up is not available 

(external pull-ups must be used).

xD Busy or Data 

Ready

xD_nB/R

28

IPU

This pin is connected to the BSY/RDY pin of the 

xD device. 

When using the internal FET, this pin has an 

internal weak pull-up resistor that is tied to the 

output of the internal Power FET, and is controlled 

by the xD_PU bit of the xDC_CTL register.

If an external FET is used (Internal FET is 

disabled), then the internal pull-up is not available 

(external pull-ups must be used).

xD Chip Enable

xD_nCE

26

O12PU

This pin is an active low chip enable signal for the 

xD device. 

When using the internal FET, this pin has an 

internal weak pull-up resistor that is tied to the 

output of the internal Power FET, and is controlled 

by the xD_PU bit of the xDC_CTL register.

If an external FET is used (Internal FET is 

disabled), then the internal pull-up is not available 

(external pull-ups must be used).

xD Card 

Detection GPIO

GPIO14 / 

xD_nCD 

29

I/O12

GPIO: This general purpose pin may be used 

either as input, edge sensitive interrupt input, or 

output.

xD_nCD: This is a GPIO designated as the xD- 

Picture Card detection pin.

MS Bus State

MS_BS

21

O12

This pin is connected to the BS pin of the MS 

device. 

It is used to control the Bus States 0, 1, 2, and 3 

(BS0, BS1, and BS3) of the MS device.

MS Card 

Insertion GPIO

GPIO12 /

MS_INS

31

IPU

GPIO: This general purpose pin may be used 

either as input, edge sensitive interrupt input, or 

output.

MS_INS: This is a GPIO designated as the 

Memory Stick card detection Pin.

MS System CLK

MS_SCLK

13

O12

This pin is an output clock signal to the MS device.

The clock frequency is software configurable.