Configuration and Operation

2.3.10.2Output I/O

A memory write to hex address 0xCC80_0000 causes U5 and U7 to latch the logic state of the data bus. Each latch output is associated with the data bus signal of the same number (Bit 0 is equal to DATA0, and so on). All output bits are forced to logic 0 (low) on power up or reset. Table 2-8shows the functions associated with each data bit.

Table 2-8. Output Latch Functions

Bit

Signal

Description

 

 

 

BIT 0

TP6

Test point

 

 

 

BIT 1

TP7

Test point

 

 

 

BIT 2

RESET_E_UART*

External UART Reset (U17)

 

 

 

BIT 3

RESET_BASE*

Ethernet controller Reset (U9)

 

 

 

BIT 4

CSI_CTL2

Image Sensor control 2

 

 

 

BIT 5

CSI_CTL1

Image Sensor control 1l

 

 

 

BIT 6

CSI_CTL0

Image Sensor control 0

 

 

 

BIT 7

UART1_EN**

UART1 transceiver enable

 

 

 

BIT 8

UART4_EN**

UART4 transceiver enable

 

 

 

BIT 9

LCDON

LCD enable

 

 

 

BIT 10

IRDA_EN**

IrDA transceiver enable

 

 

 

BIT 11

IRDA_FIR_SEL

Reserved

 

 

 

BIT 12

IRDA_MD0_B

IrDA SD/Mode (inverted)

 

 

 

BIT 13

IRDA_MD1

Reserved

 

 

 

BIT 14

LED4_ON

LED 4 control, logic 1 turns on LED

 

 

 

BIT 15

LED3_ON

LED 3 control, logic 1 turns on LED

 

 

 

*Toggle the pin from a logic 0 (low) to a logic 1 (high) and back to logic 0 to reset the selected peripheral.

**The associated x_ON switch (see Table 1-2) must be set OFF to allow the state of these bits to control the associated interface. Setting the bit to logic 1 (high) enables the interface and setting it to logic 0 (low) disables the interface.

 

M9328MX21ADSE User’s Manual, Rev. A

Freescale Semiconductor

2-11

Page 21
Image 21
Freescale Semiconductor M9328MX21ADSE Output Latch Functions, Bit Signal Description, BIT TP6, BIT TP7, BIT Reseteuart