SMSC USB2251 Computer Drive User Manual


 
Ultra Fast USB 2.0 Multi-Slot Flash Media Controller
Datasheet
Revision 1.1 (05-29-08) 14 SMSC USB2250/50i/51/51i
DATASHEET
SM Busy or Data
Ready
SM_nB/R 56 IPU This pin is connected to the BSY/RDY pin of
the SM 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 SM_PU bit of the
SMC_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).
SM Chip Enable SM_nCE 54 O12PU This pin is the active low chip enable signal
to the SM 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 SM_PU bit of the
SMC_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).
SM Card
Detection GPIO
GPIO14
(SM_nCD)
57 I/O12 This is a GPIO designated as the Smart
Media card detection pin.
MEMORY STICK INTERFACE
MS Bus State MS_BS 91 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, BS2 and BS3) of the MS
device.
MS Card
Insertion GPIO
GPIO12
(MS_INS)
98 IPU This is a GPIO designated as the Memory
Stick card detection pin.
MS System CLK MS_SCLK 101 O12 This pin is an output clock signal to the MS
device.
The clock frequency is software configurable.
MS System Data
In/Out
MS_D[7:1] 100
97
93
95
99
96
92
I/O12PD MS_D[7:0]: These pins are the bi-directional
data signals for the MS device. MS_D2 and
MS_D3 have weak pull-down resistors.
MS_D1 has a pull down resistor if it is in
parallel mode, otherwise it is disabled. In 4-
or 8-bit parallel mode, there is a weak pull-
down resistor on all MS_D7~0 signals. The
resistors are controlled by MSC_SYSTEM_0,
MSC_MODE_CTL and MSC_PRO_HG
registers.
Table 5.1 USB2250/50i/51/51i 128-Pin VTQFP Pin Descriptions (continued)
NAME SYMBOL
128-PIN
VTQFP
BUFFER
TYPE DESCRIPTION