5th Generation Hi-Speed USB Flash Media & IrDA Controller with Integrated Card Power FETs

Datasheet

Revision 1.2 (02-21-05)

18

SMSC USB2229/USB2230

DATASHEET

Memory Address

Bus

MA[1:0]/CLK_S

EL[1:0]

I/O8PD

MA[1:0], These signals address memory locations

within the external memory.

SEL[1:0]. During nRESET assertion, these pins will

select the operating frequency of the external clock, and

the corresponding weak pull-down resistors are

enabled. When nRESET is negated, the value on these

pins will be internal latched and these pins will revert to

MA[1:0] functionality, the internal pull-downs will be

disabled.

SEL[1:0] = ‘00’. 24MHz

SEL[1:0] = ‘01’. RESERVED

SEL[1:0] = ‘10’. RESERVED

SEL[1:0] = ‘11’. 48MHz

Note:

If the latched value is ‘1’, then the

corresponding MA pin is tri-stated when the

following conditions are true:

1. IDLE bit (PCON.0) is 1.

2. INT2 is negated

3. SLEEP bit of CLOCK_SEL is 1.

If the latched value is ‘0’, then the corresponding MA pin

will function identically to the MA[15:3] pins at all times

(other than during nRESET assertion).

Memory Write

Strobe

nMWR

O8

Program Memory Write; active low

Memory Read

Strobe

nMRD

O8

Program Memory Read; active low

Memory Chip

Enable

nMCE

O8

Program Memory Chip Enable; active low.

This signal is asserted, when any of the following

conditions are no longer met:

1. IDLE bit (PCON.0) is 1.

2. INT2 is negated

3. SLEEP bit of CLOCK_SEL is 1.

Note:

This signal is held to a logic ‘high’ while

nRESET is asserted.

MISC

General Purpose

I/O

GPIO1

I/O8

This pin may be used either as input, edge sensitive

interrupt input, or output.

General Purpose

I/O

GPIO2

I/O8

This pin may be used either as input, edge sensitive

interrupt input, or output.

General Purpose

I/O

GPIO3

I/O8

This pin may be used either as input, edge sensitive

interrupt input, or output.

General Purpose

I/O

GPIO4

I/O8

This pin may be used either as input, edge sensitive

interrupt input, or output.

General Purpose

I/O

GPIO5

I/O8

This pin may be used either as input, edge sensitive

interrupt input, or output.

Table 6.1 USB2229/USB2230 Pin Descriptions

NAME

SYMBOL

BUFFER

TYPE

DESCRIPTION