User manual

LPCXpresso Experiment Kit - User’s Guide

Page 86

Create a program that writes a string and reads it back to verify that the write operation was

successful. Also let the program print the content of the memory locations directly after power-up. By

doing so it is also possible to verify that the SPI E2PROM is a non-volatile memory that keeps the

content over a power cycle. Build the breadboard setup below and verify that it is possible to write and

read in the memory region on the 25LC080 chip. Note that the 330 ohm series resistor on the MISO

pin (pin 2 of the 25LC080) is not strictly needed. It is a safety precaution in case a faulty or wrong

program executes on the LPC111x, making the MISO pin an output in the LPC111x. If this happens

then the signal will have two drivers. This can cause damage to the respective pin drivers on the chips.

Figure 54 – Breadboard with SPI E2PROM