SMSC USB2250i User Manual
Page 15
Ultra Fast USB 2.0 Multi-Slot Flash Media Controller
Datasheet
SMSC USB2250/50i/51/51i
15
Revision 1.1 (05-29-08)
DATASHEET
MS System Data
In/Out
MS_D0 /
MS_SDIO
94
I/O12PD
MS_D0: This pin is one of the bi-directional
data signals for the MS device. In serial
mode, the most significant bit (MSB) of each
byte is transmitted first by either MSC or the
MS device on MS_D0, MS_D0, MS_D2, and
MS_D3 (which 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, all
MS_D7~0 signals have a weak pull-down
resistor. The resistors are controlled by
MSC_SYSTEM_0, MSC_MODE_CTL and
MSC_PRO_HG registers.
MS_SDIO: Serial Data Bus. Responsible for
transfer direction and types of data change
depending on the Bus State.
SD / MMC INTERFACE
SD Data 7-0
SD_D[7:0]
13
11
19
21
22
23
10
12
I/O12PU
These are the bi-directional data signals
SD_D0 - SD_D7.
The bi-directional signals should have weak
pull-up resistors. The register can be
controlled by the SD_MMC_INTF_EN bit of
SDC_MODE_CTL.
SD Clock
SD_CLK
18
O12
This is an output clock signal to the SD/MMC
device.
The clock frequency is software configurable.
SD Command
SD_CMD
20
I/O12PU
This is a bi-directional signal that connects to
the CMD signal of the SD/MMC device.
The bi-directional signal should have an
internal weak pull-up resistor.
The pull-up register can be controlled by:
SD_MMC_INTF_EN bit of SDC_MODE CTL.
SD Write
Protected GPIO
GPIO6
(SD_WP)
105
I/O12
This is a GPIO designated as the Secure
Digital card mechanical write detect pin.
SD Card Detect
GPIO
GPIO15
(SD_nCD)
32
I/O12
This is a GPIO designated as the Secure
Digital card detection pin.
USB INTERFACE
USB Bus Data
USB+
USB-
7
8
I/O-U
These pins connect to the USB bus data
signals.
USB Transceiver
Bias
RBIAS
127
I-R
A 12.0k, 1.0% resistor is attached from
VSSA to this pin in order to set the
transceiver's internal bias currents.
Table 5.1 USB2250/50i/51/51i 128-Pin VTQFP Pin Descriptions (continued)
NAME
SYMBOL
128-PIN
VTQFP
BUFFER
TYPE
DESCRIPTION