User manual

LPC4357 Developer’s Kit - User’s Guide

Page 11

The NAND FLASH has an optional busy output that can be used for controlling the erase/program

operations with better precision. The signal is available on the expansion connector. If needed, the

signal can be routed to a suitable (i.e., free) input pin. The OEM Base Board can connect the signal to

GPIO72 by inserting a jumper between pin 3-4 on JP2. The busy status of the chip is also available

under software control.

3.2 SPIFI

There is a 16 MBit QSPI flash connected to the SPIFI interface of the LPC4357. This memory region is

available in the following address region: 0x1400 0000 – 0x1800 0000.

3.3 Bootloader Mode Setting

There are several boot modes for the LPC4357 microcontroller. For details, read the LPC4357 User’s

manual. The LPC4357 OEM board has four sliders switches, JP1, where the boot mode can bet set.

Note that there are situations where the slider switch settings do not affect boot more. Read the

LPC4357 User’s manual for details about this, but in general the slider settings will be used to

determine the boot mode when P2_7 is pulled low during reset. This is accomplished by pulling pin

ISP_EN low, which in turn is accomplished by pressing SW6 on the OEM base board during reset. If

signal P2_7 is high during reset the LPC4357 boos from internal FLASH by default.

Schematic page 2 of the LPC4357 OEM board contains a list of the boot modes and associated slider

settings for JP1.

LED3 on the LPC4357 OEM board is connected to signal P1_1-A6-BS0, and is used by the

microcontroller to signal possible errors during booting. LED3 will flash with a 1 Hz rate for 60 seconds

if the boot process fails. After 60 seconds, the device is reset.

Slider switch JP1 is found on the top side of the LPC4357 OEM board, in the upper left corner.

Figure 1 – LPC4357 OEM Board Picture, top side

Trace connector

(Connector normally mounted)

JP1

From top to bottom;

BS0 setting

BS1 setting

BS2 setting

BS3 setting

0=’on’ pos, to the right

1=’off’ pos, to the left

J4 and J5

I2S, SGPIO and SCT expansion connectors

LED2

Memory card

interface powered