Configuration and Operation

2.3.11Audio Indicator (Buzzer)

The ADS includes an audio indicator or buzzer, U23. When S1-6 is ON, the PWMO pin of the i.MX21 controls this function. This buzzer operates from 1 KHz to 10 KHz. The maximum sound level is reached when the frequency is 3 KHz and the duty cycle is 50%.

2.3.12LED Indicators

Table 2-9shows the ADS LED indicators and their associated functions.

Table 2-9. Function of LED Indicators

Reference #

Color

Name

Function

 

 

 

 

LED1

Green

5V PWR

5 V power is ON

 

 

 

 

LED2

Green

VCC PWR

3 V power is ON

 

 

 

 

LED3

Orange

STAT 2

User status controlled by Output BIT 15*

 

 

 

 

LED4

Orange

STAT 1

User status controlled by Output BIT 14*

 

 

 

 

LED5

Green

ACTIVE

Blinking indicates LAN Activity

 

 

 

 

LED6

Orange

LINK

Link good or host controlled output

 

 

 

 

LED7

Red

BUS ACT

Blinking indicates external bus activity

 

 

 

 

*A logic high level at the controlling pin turns on the LED. A logic low turns it off.

2.4Using The Board Connectors

Table 2-10shows the ADS connectors and functions, as well as special instructions for using the connectors. Figure 1-1in Chapter 1 shows the connector locations and reference designators.

Table 2-10. M9328MX21ADSE Connectors

Connector

Function

 

Comments

 

 

 

 

P1

UART1

RS-232

DCE interface to UART1 of the i.MX21

 

 

 

 

P2

UART4

RS-232

DTE interface to UART4 of the i.MX21

 

 

 

 

P3

External UART

RS-232

DCE interface to Port A of the ST16C2552 UART

 

 

 

P4

USB OTG

USB On The Go mini AB connector

 

 

 

P5

Keypad module

Connect the Keypad ribbon cable between this connector and the

 

 

corresponding connector of the Keypad Module, J1.

 

 

 

P6

SD/MMC

Slide the MMC card into the connector until it snaps into place.

 

 

 

P7

LCD panel

Connect LCD ribbon cable between this connector and the

 

 

corresponding connector of the LCD display panel, J11.

 

 

 

P8

Power

Plug the 5-volt power-supply jack end into this connector.

 

 

 

 

 

M9328MX21ADSE User’s Manual, Rev. A

2-12

Freescale Semiconductor

Page 22
Image 22
Freescale Semiconductor M9328MX21ADSE user manual Using The Board Connectors, Audio Indicator Buzzer, LED Indicators