Questions tagged [lpc]

LPC is a series of 32-bit ARM microcontrollers manufactured by NXP Semiconductors.

Filter by
Sorted by
Tagged with
20
votes
2answers
10k views

Termination resistors: are they needed?

For a project I'm designing, I'm using an IS42s32800 (TSOP) SDRAM with an LPC1788 (QFP) microcontroller. On the PCB I have 4 layers with a ground plane right below the top signal layer and a VDD plane ...
10
votes
1answer
7k views

Storing a secure key in an embedded device's memory

I am working on an embedded device which send/receive data and stored them in ciphertext mode (encrypted mode). Now what's best approach for storing keys (I used ARM CORTEX M series MCU)? 1-Storing ...
8
votes
6answers
3k views

Is there a standard In Circuit programming connector for LPC chips?

The various LPC microcontroller chips have a boot mode that accepts serial communication and writes the received program to Flash. I want to make a PCB with and LPC1114 that must be programmed in ...
6
votes
3answers
10k views

Which ARM MCU family is better for beginners? [closed]

Which ARM MCU family is better for beginners? I mean which family: Is straightforward and easier to learn Has more/better learning and development resources available Has bigger and better ...
6
votes
1answer
423 views

What are the things to watch out for when switching from AVRs to Cortex M3?

I've just recently gotten my Cortex M3 (LPC1343) up and running, following Microbuilder's instructions to get a GNU C compiler working for it. I've run some example code and in general, the code seems ...
6
votes
2answers
907 views

LPC1788 reading via SPI from ENC28J60

I have a problem with SPI communication with ENC28J60 chip. Basically I can't use SSP in SPI mode as it is, because ENC28J60 expects CS to be low for multiple bytes while SSP shifts it high after each ...
5
votes
1answer
869 views

Can an LPC1343 accept its initial program over USB?

The LPC13xx datasheet suggests some clock setup is necessary to use USB. Does the chip's built in boot loader make it possible to load the initial program over USB, or do the clock multipliers have to ...
5
votes
3answers
6k views

Why isn't my SysTick_Handler() being called in my LPCxpresso C++ Project?

I have created a C++ project for an LPC1227 using LPCExpresso 6.1.0. The project, up until now, builds and runs fine. I have not made any changes to ...
5
votes
1answer
500 views

i2c on different logic level devices

I'm having a problem making LPC2148 work with SRF10 sensor. LPC is 3.3v device with 5v compatible i2c (at least user docu claims that). On the other side there is SRF10 device which is 5v. I have ...
4
votes
1answer
324 views

Reading useful data from barcode input

I have interfaced a HID bar-code scanner with LPC2468. It is sending data when i scan a bar-code, it sends a lot of bytes when i make a scan, how can i know out of these bytes which are the bytes ...
4
votes
2answers
2k views

ARM microcontroller, where to begin [closed]

I had previously worked on Arduino but I think it was very simplified for the users. Now, I want to learn properly. I decided to begin learning ARM microcontroller. So, I bought LPC1114 DIP because I ...
4
votes
1answer
328 views

How to get I2C to shut up while waiting for data in master transmit mode on LPC1114

I have an LPC1114(FN28) that I am writing some code for. Currently I am trying to provide an asynchronous view of the I2C interface to my code (the chip has a built-in I2C controller). The controller ...
4
votes
1answer
2k views

USB 2.0 PCB trace design restrictions

Thanks to the help from this community I am much closer to finishing my new design. Right now I am most worried about my USB 2.0 traces, and I want to make sure that I am doing everything right with ...
4
votes
1answer
230 views

Are there any open design files for an NXP LPC1* breakout board?

I would like to build a board for an LPC1* processor. Are there published Eagle layouts for these?
4
votes
1answer
4k views

RMII MAC side routing and signal integrity

I have some signal integrity and EMC questions. In my board LPC1768 RMII interface is connected to LAN8720. Because of pin locations some RMII signals must go through bottom layer. This is a four ...
4
votes
1answer
224 views

LPC1343 double pin functions

I was looking to create a LPC1343 development board, but I noticed something odd. If you look at the pinout for this MCU you can see double functions for some pins. This is common, so you can program ...
4
votes
1answer
4k views

How can I log information from code in IAR Embedded Workbench to a log file?

I'm trying to develop an application for the NXP LPC1788 microcontroller and I would like to be able to log formatted strings at arbitrary points within the source code to a log file in a way that has ...
3
votes
3answers
223 views

Choosing the right microcontroller [closed]

How do you choose a micro-controller for your project? My hardware requirements are : I2c SPI ADC channels SMD package 3.3V operating voltage A few GPIOs. There are so many microcontrollers ...
3
votes
2answers
2k views

NXP LPC 4330 Microcontroller starts up very hot and sometimes doesn't start up

EDIT 3 The correct solution is shown below, in TurboJ's answer in fact, this exact issue was mentioned in the LPC4300 errata ES_LPC43x0: EDIT: Nope, sorry false alarm. The new board started doing the ...
3
votes
1answer
90 views

ADC Burst mode in LPC2119 not working

I have been trying to work with ADC using ARM 7 LPC 2119 in burst mode however this functionality is not working. My code is as follows: ...
2
votes
2answers
310 views

FatFs f_write not working in LPC1788 Timer ISR

I’m using LPC1788 MCU with KeilV5 compiler. I Have a Timer ISR in which I read a value form specific ADC channel and write it into a SD-Card using FATFS library. Here is my Timer ISR code: ...
2
votes
3answers
767 views

Continuing execution after ISP in LPC81x series

I am uploading software via serial ISP in to an LPC81x series microcontroller. This is a Cortex-M0+ chip. After software upload, I would like to start the execution of the uploaded software without ...
2
votes
2answers
994 views

Debugging a LPC23XX based CAN bus sniffer

I am trying to get a CAN bus sniffer working, based on LPC2368. I keep getting a bus error interrupt, of type "form error". I suspect my timing settings. I verified that the sending party is ...
2
votes
1answer
1k views

Rx data rate on CAN bus faster than polling rate

I'm working on a safety-critical SIL 4 system and so interrupts have to be kept to a bare minimum (hence using only timer interrupts). CAN is used in polling mode. Suppose data arrives at a CAN node ...
2
votes
1answer
181 views

Will using a CMOS OCXO as extrnal oscillator for the XTAL input for LPC1114FN28 work?

I am trying to make a circuit which would measure the time interval between two pulses accurately. For this I have decided to use an OCXO with CMOS output and the LPC1114FN28 microprocessor. I plan ...
2
votes
1answer
596 views

LPC1788 external interrupt with CMSIS

There was a wide GPIO functions in the CMSIS initial versions which made easy setting and initialization of interrupts,like: ...
2
votes
2answers
2k views

How many device classes can a single USB composite device implement?

I'm looking to use an LPC1345 microcontroller to run a USB hub. Thanks to this question, I know that a single USB device can be used to act as multiple classes but how many? The USB hub would have ...
2
votes
1answer
872 views

Optimal configuration for PLL on LPC17xx

I'm trying to write an algorithm that would pick the best available PLL0 configuration for the user based on F_in and F_cclk. The manual says that I should pick higher F_ref if possible for a more ...
2
votes
1answer
180 views

Purpose of this coding style

I came across this piece of code for an LPCxxxx microcontroller, in the reset routine. ...
2
votes
2answers
772 views

How to automatically allocate a page of flash for in-application storage of settings

I've been using the LPC8xx range of Cortex-M0+ MCUs quite successfully. One difficiency: these don't have inbuilt EEPROM (to preserve settings across power cycles etc). However there is a work-around: ...
2
votes
1answer
160 views

Can the output of a TCXO drive a LPC1114 uC?

Is it possible to drive the on-chip oscillator of LPC1114FN28 using the clock output of a FOX924B TCXO? The Datasheet of the uC indicates that a 100 pF cap needs to be put between the oscillator and ...
2
votes
1answer
815 views

JTAG Programming with LPC4330

Because the Example Virtual Serial Device project from NXPUSBLib contains a space in it's directory structure (specifically Example_VirtualSerialDevice/LPC43xx M4/...) I can not successfully download ...
2
votes
1answer
96 views

Using a radio board with Contiki-OS on lpc1347 mcu [closed]

I am trying to build a port for Contiki on my lpc1347 board. So far I have been able to run a basic LED blinking/Hello_World Contiki process/program on my board. My next goal is to use a cc2530 radio ...
1
vote
3answers
951 views

LPC1768 Power Supply Design (an unknown symbol)

I have a question about power supply design for a board which use an LPC1768. Below image is taken from http://www.nxp.com/documents/other/IAR_LPC1768_Eval_Board_Schematic.pdf document. There is a ...
1
vote
2answers
853 views

Pin numbering on LPC2148

The pin numbers aren't listed anywhere on the board. Where's pin 1? Where's the pin for ground. This is what it looks like. This seems to list the pin numbers, but it's not really helpful in this ...
1
vote
2answers
177 views

ALU,RAM and ROM test for LPC 1778

Im working on a non safety project and as part of the Initialization tests I wanted to check the internal memory of LPC1778 for proper functionality before beginning the application. I dont intend to ...
1
vote
2answers
1k views

Output clock of the LPC1768?

I am using NXP's LPC1768 development board and I came across the User Manual for this part and page 67/849 section 4.10 descusses the External Clock Output. I couldn't figure out which pin out of the ...
1
vote
1answer
1k views

NXP LPC1114 UART doesn't work after reset

I'm building a simple circuit with LPC1114 to make a "hello world" application using UART. Trying to write all the code from scratch, to have a better understanding on what's happening. My problem is ...
1
vote
1answer
60 views

LPC2148 baud rate equation

I'm little confused about the baud rate calculating equation of LPC2148 In data sheet equation is But in every tutorial I could find equation is Second equation sets the baud rate as required. ...
1
vote
2answers
71 views

Changing pin direction without glitching on LPC800

I'm looking at an LPC812 Cortex M0+ microcontroller and its GPIO functions. On a PIC microcontroller, one would always set the LATch prior to changing the direction of a given pin. This avoids the ...
1
vote
1answer
549 views

LPC2129 CAN bus interface to OBD-II

I want to connect an LPC to the CAN bus in my car, and I found that LPC2129 have the CAN protocol implemented on the chip. Searching the Internet, I saw that most of microcontrollers are connected to ...
1
vote
1answer
102 views

Will the ADC work with resistive inputs in LPC1796

I'm working with LPC1796 and I have to do data acquisition for my project somebody told me that LPC1796 microcontroller won't work with resistive inputs. What is a resistive input? Is there any way ...
1
vote
2answers
363 views

Generating pulses via timer match output or timer ISR?

I'm using LPC1778 uC for a project and want to know what is the difference between generating pulses via timer match output and via toggling a pin in a timer ISR. What are the pros and cons of both ...
1
vote
1answer
164 views

Priority among prioritised interrupts

I am using 2 interrupts on LPC1778. One for CAN and one for timer. The CAN interrupts whenever a new message is received. The timer interrupts every 200uS. The priority for timer interrupt is the ...
1
vote
1answer
168 views

Necessary things in LPC1343 basic development board

I have finished my LPC1343 basic development board,just based on specs from datasheet and some referred from microbuilders.eu. I'm unsure if the board design is good or not so I've attached my ...
1
vote
1answer
158 views

Will a HCMOS output TCXO work with LPC1114?

I am planning to use the output from a FOX924B 10 MHz TCXO with HCMOS output as an input to the 32 bit counter of LPC 1114 (not the XTAL input, but to CT32B0_CAP0 pin). I have the following questions: ...
1
vote
1answer
1k views

USB CDC connection (plug / unplug cable)

I am having a issue with USB CDC (running in a LPC1788). If I power up a mother board with the USB cable (NXP device) already connected, the O.S. (Linux) does not identify the device, but if I unplug ...
1
vote
3answers
550 views

LPC1343 Firmware Loading - Change drive label

I have a system that is using the built-in firmware loading facility of the LPC1343. When the flash drive is mounted, the disk is always labeled "CRP_DISABLED". Is there a way to change the label of ...
1
vote
2answers
363 views

Setting I/O voltage on an embedded linux board

I'm using a LPC313x based linux board (Embedded Artists). I see in the LPC3141 DS that the I/O can be either 1.8 or 3.3V. How/where can I set the voltage level in Linux? Is the input somehow automatic?...
1
vote
1answer
100 views

Is softconnect is necessary in lpc1343

I am doing my own development board using LPC1343.I gone through the application note AN10986.I noticed the topic "Automating USB ISP".In that they described about USB softconnect. Now I am designing ...