LPC2148 - GPIO

Dr.R.Sundaramurthy.,M.E.,Ph.D., [email protected] of EIE / PEC

LPC2148 - GPIO

Dr.R.SundaramurthyDepartment of EIE

Pondicherry Engineering College

[email protected]


Parallel Port – Port 0

• Port 0 = 32 Bits (P0.0 to P0.31)

• P0.24, P0.26 and P0.27 are not available

• So (32-3) = 29 Pins are Available

• Out of 29 Pins, 28 Pins Bidirectional,

Pin 31 O/P Only


Parallel Port – Port 1

• Port 1 = 16 Bits P1.16 to P1.31

• P1.0 to P1.15 of port 1 are

• ====================================

• P0 = 29 (28 Bidirectional + 1 output only)

• P1 = 16 (16 Bidirectional)

• Total = 45 GPIOs

• ====================================


Parallel Port

P0 = 29 Pins

P1 = 16 Pins

-------------------

Total = 45 Pins

--------------------


Pins Used For GPIO in our Board

P0

P1

P2

P0.8- P0.15

P1.16- P1.23

P1.24- P1.31


SFRs Used

• IODIR1

• IOSET1

• IOCLR1

• IOPIN1

P0 P1

• IODIR0 to set the direction

• IOSET0 to set a Pin

• IOCLR 0 to clear a Pin

• IOPIN0 to Read a Pin


IODIR1 Output 0 Input

• IODIR controls the 'direction' of the GPIO pin.

• You use this register to set a GPIO pin to either Input (0) or Output (1).

• To Configure GPIO 0.10 to 'Output' (1).

GPIO0_IODIR |= (1 << 10);

• To Configure GPIO 0.10 to ‘Input' (0).

GPIO0_IODIR &= ~(1 << 10);


1 0

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

P0.0 = Input

P0.1 = Output

IODIR01 Output0 Input

Writing a 1 Pin is configured as Output

Writing a 0 Pin is configured as Input


IOSET and IOCLR

• If GPIO pin is set as Output (using the IODIR register), then

• IOSET is used to set GPIO pin to 'high'(providing a small 3.3V electrical output)

• IOCLR is used to clear it to 'low' (providing a connection to GND).


1 0

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

No Effect

Pin P0.1 = 3.3 V

IOSET0

Writing a 1 Pin is set to High

Writing a 0 No Effect


1 0

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

No Effect

Pin P0.1 = 0 V

IOCLR0

Writing a 1 Pin is cleared to Low

Writing a 0 No Effect


A small Example• // Make sure GPIO 0.10 and 0.11 are set to

output

• IODIR0 |= (1 << 10) | (1 << 11);

• // Turn the LEDs off using IOCLR (which gives a GND connection)

• IOCLR0 |= (1 << 10) | (1 << 11);

• // Turn the LEDs on using IOSET (which supplies 3.3V

• IOSET0 |= (1 << 10) | (1 << 11);


IOPIN

• Regardless of whether GPIO pin's direction is set to Input or Output,

• IOPIN register is used to read the current 'state' of every GPIO pin(all 32 pins in GPIO).

• A 1 value means that the pin is currently 'high', and a 0 value means the pin is currently 'low'.


A Small Example

int getPinState(int pinNumber) {

// Read the current state of all pins in GPIO block 0

int pinBlockState = GPIO0_IOPIN;

// Read the value of 'pinNumber'

int pinState = (pinBlockState & (1 << pinNumber)) ? 1 : 0;

// Return the value of pinState

return pinState;

}


Example Programs


LED Blink Program#include<lpc21xx.h>

void delay(void);

int main()

{

IODIR0=0xFFFFFFFF;

while(1)

{

IOSET0=0xFF00;

delay();

IOCLR0=0xFF00;

delay();

}

}

void delay(void)

{

int i;

for(i=0;i<=600000;i++);

}


P0

P1

P2

P0.8- P0.15

P1.16- P1.23

P1.24- P1.31

Pins & Ports


Ports & Pins

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 Pins

P0P1P2

For our convenience

ARM P0.8-P0.15 ARM P1.16-P0.23 ARM P1.23-P1.31


GPIO.h


List of Functions

void writepin(int pinnumber,int pinvalue);

void writeport(int portnumber,int portvalue);

int readpin(int pinnumber);

int readport(int portnumber);

void delay(void);

pinnumber = (8 to 31)

portnumber = (0 to 2)


writepinvoid writepin(int pinnumber,int pinvalue)

{

// P0 = P0.8 - P0.15

if (pinnumber >= 8 && pinnumber <= 15 )

{

IODIR0 = IODIR0 | (1 << pinnumber);

if (pinvalue)

IOSET0 = IOSET0 | (1 << pinnumber);

else

IOCLR0 = IOCLR0 | (1 << pinnumber);

}

// P1 = P1.16 - P1.23

if (pinnumber >= 16 && pinnumber <= 31 )

{

IODIR1 = IODIR1 | (1 << pinnumber);

if (pinvalue)

IOSET1 = IOSET1 | (1 << pinnumber);

else

IOCLR1 = IOCLR1 | (1 << pinnumber);

}

}


writeportvoid writeport(int portnumber,int portvalue)

{

int i;

if (portnumber == 0)

{

//P0 ==> P0.8 to P0.15

for (i=0;i<8;i++)

{

if (portvalue & 0x01 << i)

writepin(i+8,1);

else

writepin(i+8,0);

}

}

else if (portnumber == 1)

{

//P1 ==> P1.16 to P1.23

for (i=0;i<8;i++)

{


writepin(i+16,1);

else

writepin(i+16,0);

}

}

else if (portnumber == 2)

{

//P2 ==> P1.24 to P1.31

for (i=0;i<8;i++)

{


writepin(i+24,1);

else

writepin(i+24,0);

}

}

else

{

i=0 ; // dummy

}

}


readpinint readpin(int pinnumber)

{

int temp,mask ;

if (pinnumber >= 8 && pinnumber <= 15)

{

mask = ~(0x01 << pinnumber);

IODIR0 = IODIR0 & mask ; // pinnumber = input

temp = IOPIN0 ;

if (temp & (0x01 << pinnumber))

return 1 ;

else

return 0;

}

if (pinnumber >= 16 && pinnumber <= 31)

{

mask = ~(0x01 << pinnumber);

IODIR1 = IODIR1 & mask ; // pinnumber = input

temp = IOPIN1 ;

if (temp & (0x01 << pinnumber))

return 1 ;

else

return 0;

}

}


readportint readport(int portnumber)

{

int temp ;

if (portnumber == 0 )

{

//P0.8 to P0.15

IODIR0 = IODIR0 & 0xFFFF00FF;

temp = IOPIN0 ;

temp = temp & 0x0000FF00;

return (temp >> 8) ;

}

else if (portnumber == 1 )

{

//P1.16 to P1.23

IODIR1 = IODIR1 & 0xFF00FFFF;

temp = IOPIN1 ;

temp = temp & 0x00FF0000;


}

else if (portnumber == 2 )

{

//P1.24 to P1.31

IODIR1 = IODIR1 & 0x00FFFFFF;

temp = IOPIN1 ;

temp = temp & 0xFF000000;


}

else

temp=0; // dummy

}


Software delay()

void delay()

{

unsigned int i;

for(i=0;i<200000;i++);

}


Example Programs


Toggle LED @ P0.15, using software delay

#include<LPC214x.h>

#include "GPIO.h"

int main()

{

while(1)

{

writepin(15,1);

delay();

writepin(15,0);

delay();

}

}

XTAL162

XTAL261

P0.0/TxD0/PWM119

P0.1/RxD0/PWM3/EINT021

P0.2/SCL0/CAP0.022

P0.3/SDA0/MAT0..0/EINT126

P0.4/SCK0/CAP0.1/AD0.627

P0.5/MISO0/MAT0.1/AD0.729

P0.6/MOSI0/CAP0.2/AD1.030

P0.7/SSEL0/PWM2/EINT231

P0.8/TxD1/PWM4/AD1.133


P0.10/RTS1/CAP1.0/AD1.235

P0.11/CTS1/CAP1.1/SCL137

P0.12/DSR1/MAT1.0/AD1.338

P0.13/DTR1/MAT1.1/AD1.439

P0.14/DCD1/EINT1/SDA141

P0.15/RI1/EINT2/AD1.545

P0.16/EINT0/MAT0.2/CAP0.246

P0.17/CAP1.2/SCK1/MAT1.247

P0.18/CAP1.3/MISO1/MAT1.353

P0.19/MAT1.2/MOSI1/CAP1.254

P0.20/MAT1.3/SSEL1/EINT355

P0.21/PWM5/AD1.6/CAP1.31

P0.22/AD1.7/CAP0.0/MAT0.02

P0.2358

P0.25/AD0.4/AOUT9

P0.27/AD0.0/CAP0.1/MAT0.111

P0.28/AD0.1/CAP0.2/MAT0.213

P0.29/AD0.2/CAP0.3/MAT0.314

P0.30/AD0.3/EINT3/CAP0.015

V323

RST57

VREF63

VSS6

VSSA59

P1.16/TRACEPKT016

P1.17/TRACEPKT112

P1.18/TRACEPKT28

P1.19/TRACEPKT34

P1.20/TRACESYNC48

P1.21/PIPESTAT044

P1.22/PIPESTAT140

P1.23/PIPESTAT236

P1.24/TRACECLK32

P1.25/EXTIN028

P1.26/RTCK24

P1.27/TDO64

P1.28/TDI60

P1.29/TCK56

P1.30/TMS52

P1.31/TRST20

V343

V351

VSS18

VSS25

VSS42

VSS50

RTXC13

RTXC25

V3A7

VBAT49

P0.3117

P0.26/AD0.510

U1

LPC2138

+3.3V

12

X1

C1

33pF

C2

33pF

12

X2

C3

22pF

C4

22pF

R11K

C5100pF

+3.3V

D2

LED-YELLOW


Toggle LEDs @ P0, using software delay

#include<LPC214x.h>

#include "GPIO.h"

int main()

{

while(1)

{

writeport(0,0x00);

delay();

writeport(0,0xFF);

delay();

}

}

XTAL162

XTAL261

P0.0/TxD0/PWM119


P0.2/SCL0/CAP0.022


P0.4/SCK0/CAP0.1/AD0.627






P0.10/RTS1/CAP1.0/AD1.235


P0.12/DSR1/MAT1.0/AD1.338

P0.13/DTR1/MAT1.1/AD1.439


P0.15/RI1/EINT2/AD1.545


P0.17/CAP1.2/SCK1/MAT1.247




P0.21/PWM5/AD1.6/CAP1.31

P0.22/AD1.7/CAP0.0/MAT0.02

P0.2358

P0.25/AD0.4/AOUT9

P0.27/AD0.0/CAP0.1/MAT0.111

P0.28/AD0.1/CAP0.2/MAT0.213

P0.29/AD0.2/CAP0.3/MAT0.314

P0.30/AD0.3/EINT3/CAP0.015

V323

RST57

VREF63

VSS6

VSSA59

P1.16/TRACEPKT016

P1.17/TRACEPKT112

P1.18/TRACEPKT28

P1.19/TRACEPKT34

P1.20/TRACESYNC48

P1.21/PIPESTAT044

P1.22/PIPESTAT140

P1.23/PIPESTAT236

P1.24/TRACECLK32

P1.25/EXTIN028

P1.26/RTCK24

P1.27/TDO64

P1.28/TDI60

P1.29/TCK56

P1.30/TMS52

P1.31/TRST20

V343

V351

VSS18

VSS25

VSS42

VSS50

RTXC13

RTXC25

V3A7

VBAT49

P0.3117

P0.26/AD0.510

U1

LPC2138

+3.3V

12

X1

C1

33pF

C2

33pF

12

X2

C3

22pF

C4

22pF

R11K

C5100pF

+3.3V

D1

LED-YELLOWD2

LED-YELLOWD3

LED-YELLOWD4

LED-YELLOWD5

LED-YELLOWD6

LED-YELLOWD7

LED-YELLOWD8

LED-YELLOW

P0


Read Pin @ P1.31 & control @ P0.15

#include<LPC214x.h>

#include "GPIO.h"

int main()

{

int mydata;

while(1)

{

mydata = readpin(31);

if (mydata == 0)

writepin(15,1);

else

writepin(15,0);

}

}

XTAL162

XTAL261

P0.0/TxD0/PWM119


P0.2/SCL0/CAP0.022


P0.4/SCK0/CAP0.1/AD0.627






P0.10/RTS1/CAP1.0/AD1.235


P0.12/DSR1/MAT1.0/AD1.338

P0.13/DTR1/MAT1.1/AD1.439


P0.15/RI1/EINT2/AD1.545


P0.17/CAP1.2/SCK1/MAT1.247




P0.21/PWM5/AD1.6/CAP1.31

P0.22/AD1.7/CAP0.0/MAT0.02

P0.2358

P0.25/AD0.4/AOUT9

P0.27/AD0.0/CAP0.1/MAT0.111

P0.28/AD0.1/CAP0.2/MAT0.213

P0.29/AD0.2/CAP0.3/MAT0.314

P0.30/AD0.3/EINT3/CAP0.015

V323

RST57

VREF63

VSS6

VSSA59

P1.16/TRACEPKT016

P1.17/TRACEPKT112

P1.18/TRACEPKT28

P1.19/TRACEPKT34

P1.20/TRACESYNC48

P1.21/PIPESTAT044

P1.22/PIPESTAT140

P1.23/PIPESTAT236

P1.24/TRACECLK32

P1.25/EXTIN028

P1.26/RTCK24

P1.27/TDO64

P1.28/TDI60

P1.29/TCK56

P1.30/TMS52

P1.31/TRST20

V343

V351

VSS18

VSS25

VSS42

VSS50

RTXC13

RTXC25

V3A7

VBAT49

P0.3117

P0.26/AD0.510

U1

LPC2138

+3.3V

12

X1

C1

33pF

C2

33pF

12

X2

C3

22pF

C4

22pF

R11K

C5100pF

+3.3V

D2

LED-YELLOW

R21K

+3.3V


Read Pin @ P1.31 & control @ P0.15

#include<LPC214x.h>

#include "GPIO.h"

int main()

{

int mydata;

while(1)

{

mydata = readpin(31);

if (mydata == 0)

writepin(15,1);

else

writepin(15,0);

}

}

XTAL162

XTAL261

P0.0/TxD0/PWM119


P0.2/SCL0/CAP0.022


P0.4/SCK0/CAP0.1/AD0.627






P0.10/RTS1/CAP1.0/AD1.235


P0.12/DSR1/MAT1.0/AD1.338

P0.13/DTR1/MAT1.1/AD1.439


P0.15/RI1/EINT2/AD1.545


P0.17/CAP1.2/SCK1/MAT1.247




P0.21/PWM5/AD1.6/CAP1.31

P0.22/AD1.7/CAP0.0/MAT0.02

P0.2358

P0.25/AD0.4/AOUT9

P0.27/AD0.0/CAP0.1/MAT0.111

P0.28/AD0.1/CAP0.2/MAT0.213

P0.29/AD0.2/CAP0.3/MAT0.314

P0.30/AD0.3/EINT3/CAP0.015

V323

RST57

VREF63

VSS6

VSSA59

P1.16/TRACEPKT016

P1.17/TRACEPKT112

P1.18/TRACEPKT28

P1.19/TRACEPKT34

P1.20/TRACESYNC48

P1.21/PIPESTAT044

P1.22/PIPESTAT140

P1.23/PIPESTAT236

P1.24/TRACECLK32

P1.25/EXTIN028

P1.26/RTCK24

P1.27/TDO64

P1.28/TDI60

P1.29/TCK56

P1.30/TMS52

P1.31/TRST20

V343

V351

VSS18

VSS25

VSS42

VSS50

RTXC13

RTXC25

V3A7

VBAT49

P0.3117

P0.26/AD0.510

U1

LPC2138

+3.3V

12

X1

C1

33pF

C2

33pF

12

X2

C3

22pF

C4

22pF

R11K

C5100pF

+3.3V

D2

LED-YELLOW

R21K

+3.3V


Read Port @ P0 & control @ P1,P2

#include<LPC214x.h>

#include "GPIO.h"

int main()

{

int mydata;

while(1)

{

mydata = readport(0);

if (mydata < 128)

writeport(1,mydata);

else

writeport(2,mydata);

}

}

XTAL162

XTAL261

P0.0/TxD0/PWM119


P0.2/SCL0/CAP0.022


P0.4/SCK0/CAP0.1/AD0.627






P0.10/RTS1/CAP1.0/AD1.235


P0.12/DSR1/MAT1.0/AD1.338

P0.13/DTR1/MAT1.1/AD1.439


P0.15/RI1/EINT2/AD1.545


P0.17/CAP1.2/SCK1/MAT1.247




P0.21/PWM5/AD1.6/CAP1.31

P0.22/AD1.7/CAP0.0/MAT0.02

P0.2358

P0.25/AD0.4/AOUT9

P0.27/AD0.0/CAP0.1/MAT0.111

P0.28/AD0.1/CAP0.2/MAT0.213

P0.29/AD0.2/CAP0.3/MAT0.314

P0.30/AD0.3/EINT3/CAP0.015

V323

RST57

VREF63

VSS6

VSSA59

P1.16/TRACEPKT016

P1.17/TRACEPKT112

P1.18/TRACEPKT28

P1.19/TRACEPKT34

P1.20/TRACESYNC48

P1.21/PIPESTAT044

P1.22/PIPESTAT140

P1.23/PIPESTAT236

P1.24/TRACECLK32

P1.25/EXTIN028

P1.26/RTCK24

P1.27/TDO64

P1.28/TDI60

P1.29/TCK56

P1.30/TMS52

P1.31/TRST20

V343

V351

VSS18

VSS25

VSS42

VSS50

RTXC13

RTXC25

V3A7

VBAT49

P0.3117

P0.26/AD0.510

U1

LPC2138

+3.3V

12

X1

C1

33pF

C2

33pF

12

X2

C3

22pF

C4

22pF

R11K

C5100pF

+3.3V

D9

LED-YELLOWD10

LED-YELLOWD11

LED-YELLOWD12

LED-YELLOWD13

LED-YELLOWD14

LED-YELLOWD15

LED-YELLOWD16

LED-YELLOW

P1

D17

LED-YELLOWD18

LED-YELLOWD19

LED-YELLOWD20

LED-YELLOWD21

LED-YELLOWD22

LED-YELLOWD23

LED-YELLOWD24

LED-YELLOW

P2

R210k

+3.3v

R310k

+3.3v

R410k

+3.3v

R510k

+3.3v

R610k

+3.3v

R710k

+3.3v

R810k

+3.3v

R910k

+3.3v

P0


End of Session

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LPC2148 - GPIO