LPC2138 GPIO Pull Downs ?

Started by nknight62 in LPC200012 years ago 4 replies

We have an application where we use the GPIO I/O pins on Port 1 of LPC2138 to an LCV244 buffer/driver. We found that randomly, some pins on...

We have an application where we use the GPIO I/O pins on Port 1 of LPC2138 to an LCV244 buffer/driver. We found that randomly, some pins on the buffer driver were high or low at power-up with no program loaded to control the pins. We added 32k pull downs between the 2138 and the buffer/driver inputs to pull the lines low because the GPIO lines are floating inputs before program change


Port 1 of LPC 2148 completely switched to GPIO does not work.

Started by "joerg.nagel" in LPC200012 years ago 42 replies

Hello all, I am totally messed up. I am trying to use Port1 (P1.16 to P1.31) of an LPC2148 as GPIO. I am trying for about two weeks now without...

Hello all, I am totally messed up. I am trying to use Port1 (P1.16 to P1.31) of an LPC2148 as GPIO. I am trying for about two weeks now without success. I am using the arm-elf-gcc ver. 4.0.2 for windows. I took the startup assembly code from the "Hello World!" example downloadable in the files section of this group. My hardware layout is similar to the olimex LPC-P2148 eval board. In the m...


Optimising GPIO on LPC1343 (Cortex M3)

Started by kevin_townsend2 in LPC20008 years ago 7 replies

I've been working on a TFT LCD driver (ILI9325) using an 8-bit interface, and have been able to get it up to about 15fps @ 72MHz paying attention...

I've been working on a TFT LCD driver (ILI9325) using an 8-bit interface, and have been able to get it up to about 15fps @ 72MHz paying attention to how I set GPIO (single cycle clear+set as described in section 8.5.1 of the 1343 UM, etc.). Compiling with no optimisation (GCC 4.4), it still feels kind of slow with the cmd method taking 40 cycles. Since this function is very heavily used, I was w...


LPC2129 GPIO issues with P0.2 and P0.4

Started by berney73 in LPC200012 years ago 6 replies

Currently I have an LPC2129 and am trying to use the P0.2/SCL and P0.3/SDA/Eint1 pins for GPIO. Running the software under simulation in KEIL...

Currently I have an LPC2129 and am trying to use the P0.2/SCL and P0.3/SDA/Eint1 pins for GPIO. Running the software under simulation in KEIL shows the micro correctly changing the states of these pins however once applied to the physical chip on a board we've designed in house there's no signal - basically ground with a little noise. I've been over the schematics (as I didnt design t


GPIO port speed

Started by Zoltan R in LPC200012 years ago 7 replies

Dear Members, I am using LPC2106 and trying to achieve the highest possible speed on GPIO port with the following code: IOSET =...

Dear Members, I am using LPC2106 and trying to achieve the highest possible speed on GPIO port with the following code: IOSET = 0xFFFFFFFF; IOCLR = 0xFFFFFFFF; It results a ~990 ns wide pulse. Is it possible to achieve less? If so, how can I do that? BR, Zoltan Raics --------------------------------- Do you Yahoo!? Everyone is raving about the all-new...


LPC2387 GPIO interrupt latency

Started by "ger...@yahoo.gr [lpc2000]" in LPC20004 years ago 8 replies

Hi everyone I have found that a GPIO interrupt sharing EXTINT3 with the highest priority has about 60usec. latency instead of EXTINT3 pin. Can...

Hi everyone I have found that a GPIO interrupt sharing EXTINT3 with the highest priority has about 60usec. latency instead of EXTINT3 pin. Can this feature be fixed?Is there any method? I am trying to interface a barcode reader and I am loosing always the 1st clock. I am using gcc gnu arm with eclipse IDE. Thanks In Advance Chris


SSEL1 functionally

Started by javida13 in LPC200013 years ago 2 replies

The manual states that for the SSEL0 signal, that when SPI is setup as a Master, this signal can be used as GPIO. This statement is not...

The manual states that for the SSEL0 signal, that when SPI is setup as a Master, this signal can be used as GPIO. This statement is not in the description of the SSEL1 signal. I'm configurating the SSP as an SPI port and would like to use SSEL1 as a GPIO pin. Any experience? Barry


Re: Fast GPIO on LPC2138/01 - many problems

Started by Alexander Whiplash in LPC200010 years ago 3 replies

----- Original Message ---- From: Paul Curtis To: l...@yahoogroups.com Sent: Tuesday, February 12, 2008 1:24:18 PM Subject: RE:...

----- Original Message ---- From: Paul Curtis To: l...@yahoogroups.com Sent: Tuesday, February 12, 2008 1:24:18 PM Subject: RE: [lpc2000] Fast GPIO on LPC2138/01 - many problems Hi, > I am having quite a few problems with the simplest port IO on this > LPC2138/01 CPU. I have a complete application running and it is > almost usable except for not being able t


Strange SPI behavior and slow gpio

Started by rkdwork in LPC200014 years ago 3 replies

Hi, I have been developing software to perform SPI transfers. I am using a logic analyzer to examine the SCLK, MOSI, MISO and...

Hi, I have been developing software to perform SPI transfers. I am using a logic analyzer to examine the SCLK, MOSI, MISO and gpio signals. The board I am using is an IAR Kickstart card with a 14.7MHz clock. The first thing that I found was that if I set the SOSPCCR counter


Trouble with P0.2 as GPIO

Started by rkd0930home in LPC200014 years ago 4 replies

Hi All, I am having difficulty with controlling pin P0.2 as a GPIO output signal. I am successfully controlling several other...

Hi All, I am having difficulty with controlling pin P0.2 as a GPIO output signal. I am successfully controlling several other pins on my board. I have set bit 4 and 5 of PINSEL0 to zero. I have set bit 2 of IO0DIR to 1 and I have set bit 2 of IO0SET to 1. P0.2 stays at zero


GPIO P0.3 problem

Started by MattKav in LPC200013 years ago 3 replies

I am trying to use P0.3 as a GPIO, but it doesn't seem to be working. I define the bit as: #define ADC_CS (1 << 3) but it doesn't work. If I change it to: #define...

I am trying to use P0.3 as a GPIO, but it doesn't seem to be working. I define the bit as: #define ADC_CS (1 << 3) but it doesn't work. If I change it to: #define ADC_CS (1 << 19) I can toggle it just fine using the exact same code. P0.2 does not work either. I am not using the I2C, but I am using SPI. I am using Timer0; howev


P1.20/TRACESYNC low GPIO

Started by brobinson323 in LPC200011 years ago

Hi, It's safe to pull the P1.20/TRACESYNC in lpc2138 low while reset and then using the firmware change PSEL2 = 0 to GPIO. I am using the...

Hi, It's safe to pull the P1.20/TRACESYNC in lpc2138 low while reset and then using the firmware change PSEL2 = 0 to GPIO. I am using the P1.16 -P1.23 to drive a darlington drive uln2308 chip, which have a pull down resistor build -in. I have haven't experiencing any problem yet but I only tested this only in a few boards. Anyone use P1.15 - P1.23 similar to me, which need to pull the pins...


Re: Interview Questions

Started by Bhanu in LPC200010 years ago 2 replies

=A0Sir, I know the answers. I explained the answers as follow to interviewer= also.But interviewer asked me can you tell me the other...

=A0Sir, I know the answers. I explained the answers as follow to interviewer= also.But interviewer asked me can you tell me the other answers. Interrupt will depend upon the hardware. Assume that I want to go to an int= errupt when an GPIO goes low.Means the hardware will wait until the GPIO be= come low. Where as an function will execute when we call it. The purpose of watch...


How to set GPIO pin P0.8 and P0.9 to high and low on LPC2103

Started by Santos Kumar Das in LPC200010 years ago 1 reply

Dear All, I'm having problem to use "fast" GPIO on my LPC2103. I need to set GPIO pin P0.8 and P0.9 to high and low, but couldn't make...

Dear All, I'm having problem to use "fast" GPIO on my LPC2103. I need to set GPIO pin P0.8 and P0.9 to high and low, but couldn't make it. Following are several ways, which I tried but can't see the high or low at the pins. 1. PINSEL0 = (PINSEL0 && 0xFFFFFEFF) || 0x00000100; FIODIR = (FIODIR && 0xFFFFFEFF) || 0x00000100; FIOCLR = (FIOCLR && 0xFFFFFEFF) || 0x00000100; FIOSET =...


Re: Using TRST (P1.31) as GPIO on LPC2148

Started by Thiago in LPC200011 years ago

Maybe this informations can help you: Take a look at LPC2148 User Manual, page 80: PINSEL2 register, bit 2, is used to set the direction of...

Maybe this informations can help you: Take a look at LPC2148 User Manual, page 80: PINSEL2 register, bit 2, is used to set the direction of PIN 1.36-1.26 The GPIO 1.23 is controlled by bit 3 of PINSEL2. If P0.31 were externally pulled low, when reset, the JTAG is going to be disabled (page 72). Thiago Lima. Electrical Engineer ashwin athani wrote: > > Hi all, > > Has anybod


i2c pins in GPIO mode

Started by Ali Aghayifar in LPC20008 years ago 1 reply

Hi i program this code in my lpc2148 : SCS|=1; FIO0DIR =0xFFFFFFFF; FIO0SET = 0xFFFFFFFF; every pin were 1 and 3V but p0.2 and po.3 also...

Hi i program this code in my lpc2148 : SCS|=1; FIO0DIR =0xFFFFFFFF; FIO0SET = 0xFFFFFFFF; every pin were 1 and 3V but p0.2 and po.3 also po.11 and p0.14 did not appear 1 and couldn't turn on a LED all of this 4 pins are for I2C bus in GPIO mode , this pin need to be pull up ?or no THX ------------------------------------


LPC1766 Example Code does not run (Keil V3.50)

Started by Alex Ribero in LPC20009 years ago 6 replies

Hi: For those of you that got your sample of the LPC1766.... I installed my sample on a board and tried to run the Blinky example provided...

Hi: For those of you that got your sample of the LPC1766.... I installed my sample on a board and tried to run the Blinky example provided by Keil for the LPC1766. The program compiles and is programmed in Flash Memory. However, the GPIO pins do not toggle as expected. Using the debugger, I am able to step through the beginning of main, but when it reaches a GPIO register access, it fa...


VIC on the LPC2478

Started by "jim.deas" in LPC20009 years ago 5 replies

Can someone give me a hand with the VIC on this chip? I want to attach a GPIO to trigger an interrupt just to get the feel of the chip. I init'...

Can someone give me a hand with the VIC on this chip? I want to attach a GPIO to trigger an interrupt just to get the feel of the chip. I init' the chips like this. '--------------------------------------------------------- //Set a mask for the two buttons on the development card PINSEL5 = 0x00;//Set P2[16]-P1[31] to GPIO PINMODE5 = 0x00;//Set pull up resistor enabled FIO2MASK = ~(BUT1_MA...


Re: Fast GPIO scaning speed of LPC2478

Started by Alex in LPC20007 years ago

Hi Actually 72MHz is 13.88ns not 0.138ns Best regards Alex ----- Original Message ----- From: mohammed fazal To:...

Hi Actually 72MHz is 13.88ns not 0.138ns Best regards Alex ----- Original Message ----- From: mohammed fazal To: l...@yahoogroups.com Sent: Friday, March 25, 2011 5:17 PM Subject: Re: [lpc2000] Re: Fast GPIO scaning speed of LPC2478 Hello Bernardo, Your view of thinking is Okay? Please think the points below, 1) LPC2478 CPU running @ ...


LPC2119 GPIO 5V tolerance

Started by Gerhard Uttenthaler in LPC200013 years ago

Hi, we have build a system with the LPC2119, where we connect a 5V Signal to a GPIO. Now when the system starts, the 5V is present...

Hi, we have build a system with the LPC2119, where we connect a 5V Signal to a GPIO. Now when the system starts, the 5V is present a little bit earlier than the 3.3V. Could this be a problem for the device, because in the Limiting Values for this device the 5V tolerance is only specified when the 3.3V is present. Another question