Power Control & GPIO pins

Started by Leighton Rowe in LPC200014 years ago 4 replies

I heard that pull ups are needed to run P0.2 & 3 as regular GPIO pins, since they are part of the I2C interface. Given the board...

I heard that pull ups are needed to run P0.2 & 3 as regular GPIO pins, since they are part of the I2C interface. Given the board I'm working with...I might not have the luxury to make that hardware change. Isn't there another way (without using pull ups)? How about


LPC2468 GPIO

Started by coli...@arrisi.com in LPC20008 years ago 5 replies

Hi, I'm a noob in this group and with LPC micros for forgive me if this sounds a little basic. Have been tearing my hair out trying to set D0-D7...

Hi, I'm a noob in this group and with LPC micros for forgive me if this sounds a little basic. Have been tearing my hair out trying to set D0-D7 (P3.0 - P3.7) as GPIO inputs on LPC2468. Using keil, have the following config PINSEL6 = 0x5555; /*enable D0=D7*/ FIO3DIR &= ~((1UL <


GPIO TOGGLING PROBLEM

Started by PATEL VIPUL in LPC200011 years ago 3 replies

Hi all, I am using LPC2101 for my application in which i have to use P0.0 to P0.3. And here is the code just for testing these pins. ...

Hi all, I am using LPC2101 for my application in which i have to use P0.0 to P0.3. And here is the code just for testing these pins. PINSEL0 = 0; // Make all pins GPIO function IODIR = 0x0F; // Make P0.0-P1.3 as output while(1) { if(flag==0) { IOSET = 0X0F; flag=1; } else { IOCLR = 0X0F; flag=0; } ...


FreeRTOS GPIO Interrupt, LPC2378

Started by Baishun Wu in LPC20007 years ago 7 replies

Hello, I am currently working on a board with LPC2378 using FreeRTOS. I would like to do interrupt for GPIO port 2.2 and 2.3 at both falling...

Hello, I am currently working on a board with LPC2378 using FreeRTOS. I would like to do interrupt for GPIO port 2.2 and 2.3 at both falling and rising edge. I have tested the reading of the ports work well. But the interrupt part never works. The following is a my code: // All the include stuffs void readPos()__attribute__((naked)); int trigger; int main(){ // initialize G...


LPC2366 PWM ~1uS low going glitch

Started by bobtransformer in LPC20008 years ago 8 replies

Hi guys... In my timer0 interrupt, when I try to turn the PWM output back into a GPIO (Fast GPIO) and set it high, I sometimes get a 1...

Hi guys... In my timer0 interrupt, when I try to turn the PWM output back into a GPIO (Fast GPIO) and set it high, I sometimes get a 1 microsecond low going glitch. Even if I read the pin first to make sure I am not catching the PWM in the middle of a LOW portion of a cycle first. The external circuitry does not want to see this short glitch. Any thoughts ?? A better way maybe ? Th...


LPC2129: Software Uart

Started by pradeep in LPC200011 years ago 1 reply

i am new to lp2129/microcontrollers i am trying to transmit a character (let 0x39) using lpc219 with out using on-chip peripheral uart for...

i am new to lp2129/microcontrollers i am trying to transmit a character (let 0x39) using lpc219 with out using on-chip peripheral uart for this i have programmed the on-chip timer to give interrupts at the rate of 9600 bps(i have kept timer value as C35 for this) and i am changing the value on the gpio port with the required bit value (for 0x39 i am placing 00011100111 on the gpio one bit a...


LPC2148

Started by alan_in_nz in LPC200013 years ago 6 replies

I am using an LPC2148 with a 32.768KHz crystal on the RTC oscillator pins. I need to internally route the resulting 32.768KHz clock and...

I am using an LPC2148 with a 32.768KHz crystal on the RTC oscillator pins. I need to internally route the resulting 32.768KHz clock and output it to a GPIO pin. Is this possible? If so how and what pin is best to use as the output GPIO pin? The datasheet I have been looking at does not seem to have (as far as I can see) a detailed block diagram which shows the clock schemes for this dev


LPC2103 GPIO Timing

Started by Fred Quimby in LPC200011 years ago

I'm writing a time-sensitive driver and as such it will be 100% asm. As fa= r as cycle counts go, things should work, and simulation is 100%...

I'm writing a time-sensitive driver and as such it will be 100% asm. As fa= r as cycle counts go, things should work, and simulation is 100% spot-on, b= ut the hardware doesn't talk properly. I want to rule out bus contention or violation of setup/hold times, but I c= an't find anything about how long the LPC2103 takes to release the bus when= GPIO (fast or slow) is set to input mode, o...


Accessing external peripherals through LPC2292

Started by Unnati Shah in LPC20009 years ago

Hi, I am using LPC2292 to interface with a graphic display. The hardware interface is as follows: LPC2292 Pin ...

Hi, I am using LPC2292 to interface with a graphic display. The hardware interface is as follows: LPC2292 Pin Display Pin P2.0-P2.7 as D0-D7 D0-D7 data lines P1.1 as OE \RD read enable P3.27 as WE \WR write enable P3.0 as GPIO \CS chip select P0.29 as GPIO ...


GPIO - possible to change RESET default pull up?

Started by Markus Zingg in LPC200010 years ago 4 replies

Hi group, I'm of course aware of the pin mode select register which allows me to define wether a given GPIO pin is haveing a pull up, down,...

Hi group, I'm of course aware of the pin mode select register which allows me to define wether a given GPIO pin is haveing a pull up, down, none etc. The question I have centers more around the behaviour of the pins bevore any initializing code can take influence. I mean, is there a strapping pin or something I have overseen so far that would allow me to change the reset default from ...


GPIO Interrupt lpc1768

Started by "maike.drewitz" in LPC20008 years ago 7 replies

Hey, i want to generate a GPIO Interrupt at the raising edge on Port2.10 and at the falling edge on Port0.21. Is this posible? I have tried it...

Hey, i want to generate a GPIO Interrupt at the raising edge on Port2.10 and at the falling edge on Port0.21. Is this posible? I have tried it that way but it doesn't run, maybe anyone can take a look at this and help me, thanks =) LPC_PINCON-> PINSEL4 = 0x01000000; // set P2.12 as EINT2 LPC_GPIOINT-> IO2IntEnF = 0x1400; // Port2.12 und 2.10 falling edge LPC_GPIOINT-> IO0IntEnF = 0x200


GPIO behavior

Started by gen_4p in LPC200012 years ago 3 replies

Hi, I am doing some development on Keil lpc2148 development board. I use P0.2,3 as GPIO out (slow GPIOs) ans set them high at certain point....

Hi, I am doing some development on Keil lpc2148 development board. I use P0.2,3 as GPIO out (slow GPIOs) ans set them high at certain point. At a breakpoint (ULINK) I see bits 2,3 set for this pins in both IODIR0 and IOSEL0, and see that they are set as GPIOs in Pin Select Block. Nevertheless a scope shows that pins are low. Could it be any other explanation for this behavior except that...


Configuring GPIO on lpc2468

Started by khader_s_s in LPC200011 years ago 6 replies

Hi I have an lpc2468 board where I have uart0 and a GSM module connected to uart1 and a GPS module connected to uart2 where UART0= P0.2 ~...

Hi I have an lpc2468 board where I have uart0 and a GSM module connected to uart1 and a GPS module connected to uart2 where UART0= P0.2 ~ P0.3 UART1= P2.0 ~ P2.7 UART2= P0.10 ~ P0.11 UART3= P0.25 ~ P0.26 I am trying set GPIO for this. PINSEL0 |= 0x00500050; /* P0.2 TXD0 , P0.3 RXD0 & P0.10 TXD2 , P0.11 RXD2 */ PINSEL1 |= 0x003b0000; /* P0.25 TXD3 , P0.26 R...


SPI Configuration Question?

Started by Bill Knight in LPC200013 years ago

A quick question to the group, if I may. When an SPI is used for read only (MISO, SCK, & SSEL), can the pin normally occupied by MOSI be...

A quick question to the group, if I may. When an SPI is used for read only (MISO, SCK, & SSEL), can the pin normally occupied by MOSI be used as a GPIO pin? I am providing an off board interface to a varity of different sensor configurations and in this case would like to use the MOSI pin (configured as a GPIO pin) as a enable to the sensor.


LPC17xx: PCONP and GPIO enable

Started by "M. Manca" in LPC20008 years ago

I made a mistake writing a wrong value on PCONP register on a LPC1754 so I discovered that BIT15 of PCONP enables or disables (enables if...

I made a mistake writing a wrong value on PCONP register on a LPC1754 so I discovered that BIT15 of PCONP enables or disables (enables if its value is 1 disables if is 0) the power to all GPIO ports. On page 118 of UM10360 it is written: Power always enabled. Obviously UM is wrong. The problem: is this a not documented feature or is it an hardware error? Just to understand what behaviour I c...


Re: LPC17xx: PCONP and GPIO enable

Started by doug...@gmail.com in LPC20008 years ago

I made a mistake writing a wrong value on PCONP register on a LPC1754 so > I discovered that BIT15 of PCONP enables or disables (enables if...

I made a mistake writing a wrong value on PCONP register on a LPC1754 so > I discovered that BIT15 of PCONP enables or disables (enables if its > value is 1 disables if is 0) the power to all GPIO ports. > On page 118 of UM10360 it is written: Power always enabled. > Obviously UM is wrong. > The problem: is this a not documented feature or is it an hardware > error? Just to understand what beh


LPC2468 LCD and GPIO

Started by "marcin.stepien" in LPC200010 years ago 1 reply

Hi. I want to use LCD interface from LPC2478 configured as 12bit(4:4:4 mode) for my LCD module. LCDVD[3:0], LCDVD[11:8], LCDVD[19:16] is not...

Hi. I want to use LCD interface from LPC2478 configured as 12bit(4:4:4 mode) for my LCD module. LCDVD[3:0], LCDVD[11:8], LCDVD[19:16] is not used for LCD interface in 12 bit(4:4:4 mode TFT). So, can i use them for GPIO? Marcin Stepien ------------------------------------


LPC2xxx GPIO Outputs Born LOW

Started by markcrow in LPC200014 years ago 9 replies

I was surprised to discover that GPIO pins, just after they're configured as outputs, default LOW (the opposite state of its...

I was surprised to discover that GPIO pins, just after they're configured as outputs, default LOW (the opposite state of its startup high-impedance input mode). For my design, LOW is an ACTIVE state. I can immediately set the output HIGH but I'm stuck with a LOW 'glitch' t


LPC2300 FGPIO, PU/PD and power consumption

Started by Marko Pavlin in LPC200010 years ago 4 replies

Hello! In order to reduce current flow in GPIO would it be OK if I change pull-up and pull-down at GPIO pin depending on curent state? Pins...

Hello! In order to reduce current flow in GPIO would it be OK if I change pull-up and pull-down at GPIO pin depending on curent state? Pins are outputs andv they are driving low power FET gates (almost statically): When pin is cleared (0), pull-down is used and vice versa. Is this OK to reduce some power consumption? Marko ------------------------------------


LPC2458 sleep mode

Started by Himanshu Patel in LPC20009 years ago 2 replies

Hi All, We are working on power management of LPC2458 sleep. We are presently getting power down current around 2 mA which is quite higher...

Hi All, We are working on power management of LPC2458 sleep. We are presently getting power down current around 2 mA which is quite higher than theoretical value of around 500 uA. We have done following things to put the LPC2458 in the power down mode: a) State : power down mode b) GPIO: un-used GPIO pins are in input mode and configured as active low. c) ADC: converted ...