@@ -1,7 +1,7 @@ | |||
/* | |||
* pcf8574.c: | |||
* Extend wiringPi with the PCF8574 I2C GPIO expander chip | |||
* Copyright (c) 2013 Gordon Henderson | |||
* Copyright (c) 2013-2024 Gordon Henderson and contributors | |||
*********************************************************************** | |||
* This file is part of wiringPi: | |||
* https://github.com/WiringPi/WiringPi/ | |||
@@ -33,8 +33,9 @@ | |||
/* | |||
* myPinMode: | |||
* The PCF8574 is an odd chip - the pins are effectively bi-directional, | |||
* however the pins should be drven high when used as an input pin... | |||
* The PCF8574 is a 8-Bit I/O Expander with Open-drain output. | |||
* The pins are effectively bi-directional, | |||
* however the pins should be driven high when used as an input pin... | |||
* So, we're effectively copying digitalWrite... | |||
********************************************************************************* | |||
*/ | |||
@@ -102,7 +103,7 @@ static int myDigitalRead (struct wiringPiNodeStruct *node, int pin) | |||
* pcf8574Setup: | |||
* Create a new instance of a PCF8574 I2C GPIO interface. We know it | |||
* has 8 pins, so all we need to know here is the I2C address and the | |||
* user-defined pin base. | |||
* user-defined pin base. Default address (A0-A3 low) is 0x20. | |||
********************************************************************************* | |||
*/ | |||
@@ -6,7 +6,9 @@ tests = wiringpi_test1_sysfs wiringpi_test2_sysfs wiringpi_test3_device_wpi wiri | |||
xotests = wiringpi_xotest_test1_spi | |||
all: $(tests) $(xotests) | |||
i2ctests = wiringpi_i2c_test1_pcf8574 | |||
all: $(tests) $(xotests) $(i2ctests) | |||
wiringpi_test1_sysfs: | |||
${CC} ${CFLAGS} wiringpi_test1_sysfs.c -o wiringpi_test1_sysfs -lwiringPi | |||
@@ -32,6 +34,9 @@ wiringpi_test7_version: | |||
wiringpi_xotest_test1_spi: | |||
${CC} ${CFLAGS} wiringpi_xotest_test1_spi.c -o wiringpi_xotest_test1_spi -lwiringPi | |||
wiringpi_i2c_test1_pcf8574: | |||
${CC} ${CFLAGS} wiringpi_i2c_test1_pcf8574.c -o wiringpi_i2c_test1_pcf8574 -lwiringPi | |||
test: | |||
@error_state=false ; \ | |||
for t in $(tests) ; do \ | |||
@@ -51,7 +56,7 @@ test: | |||
xotest: | |||
@error_state=false ; \ | |||
for t in $(tests) $(xotests) ; do \ | |||
echo === unit test: $${t} === ; \ | |||
echo === XO unit test: $${t} === ; \ | |||
time ./$${t} ; \ | |||
if [ $$? -ne 0 ]; then \ | |||
error_state=true ; \ | |||
@@ -64,7 +69,23 @@ xotest: | |||
echo "\n\e[5mSTD/XO TEST SUCCESS\e[0m\n"; \ | |||
fi | |||
i2ctest: | |||
@error_state=false ; \ | |||
for t in $(tests) $(i2ctests) ; do \ | |||
echo === I2C unit test: $${t} === ; \ | |||
time ./$${t} ; \ | |||
if [ $$? -ne 0 ]; then \ | |||
error_state=true ; \ | |||
fi ; \ | |||
echo ; echo ; \ | |||
done | |||
if [ "$$error_state" = true ]; then \ | |||
echo "\n\e[5mSTD/I2C TEST FAILED\e[0m\n"; \ | |||
else \ | |||
echo "\n\e[5mSTD/I2C TEST SUCCESS\e[0m\n"; \ | |||
fi | |||
clean: | |||
for t in $(tests) $(xotests) ; do \ | |||
for t in $(tests) $(xotests) $(i2ctests) ; do \ | |||
rm -fv $${t} ; \ | |||
done |
@@ -0,0 +1,112 @@ | |||
// WiringPi test program: I2C functions (need PCF8574) | |||
// Compile: gcc -Wall wiringpi_i2c_test1.c -o wiringpi_i2c_test1 -lwiringPi | |||
#include "wpi_test.h" | |||
#include "pcf8574.h" | |||
#include "wiringPiI2C.h" | |||
const int pinBase = 1020; | |||
const int i2cAdress = 0x20; | |||
int ShowAll() { | |||
int in; | |||
int value = 0; | |||
printf("pin: 0 1 2 3 4 5 6 7\nval: "); | |||
for (int pin=0; pin<=7; ++pin) { | |||
in = digitalRead(pinBase + pin); | |||
printf("%d ", in); | |||
if(in==HIGH) { value |= (0x01<<pin); } | |||
} | |||
printf(" = 0x%02X\n", value); | |||
return value; | |||
} | |||
void testPin(const char* msg, int fd, int pin , int value) { | |||
printf("%s:\n", msg); | |||
int in = digitalRead(pinBase + pin); | |||
CheckSame("digitalRead", in, value); | |||
int expect = HIGH==value ? (0x1<<pin) : 0; | |||
int pinmask = 0x01<<pin; | |||
int i2cread = wiringPiI2CRead(fd); | |||
CheckSame("wiringPiI2CRead", i2cread & pinmask, expect); | |||
//printf("Value = 0x%X\n",i2cread); | |||
uint8_t i2cvalue = HIGH==value ? 0x00 : 0xFF; | |||
int result = wiringPiI2CRawRead(fd, &i2cvalue, 1); | |||
CheckSame("wiringPiI2CRawRead result", result, 1); | |||
CheckSame("wiringPiI2CRawRead", i2cvalue & pinmask, expect); | |||
//printf("Value = 0x%X\n",i2cvalue); | |||
} | |||
int main (void) { | |||
int major, minor; | |||
wiringPiVersion(&major, &minor); | |||
printf("Testing I2C functions with PCF8574 (WiringPi %d.%d)\n",major, minor); | |||
printf("-------------------------------------------------\n\n"); | |||
int ret = pcf8574Setup (pinBase, i2cAdress); | |||
if (ret!=1) { | |||
FailAndExitWithErrno("pcf8574Setup", ret); | |||
} | |||
int fd = wiringPiI2CSetup (i2cAdress); | |||
if (fd<=0) { | |||
FailAndExitWithErrno("wiringPiI2CSetup", fd); | |||
} | |||
CheckSame("I2C fd", fd, 4); | |||
ShowAll(); | |||
int pin = 3; | |||
testPin("Test pin 3 high", fd, pin , HIGH); | |||
testPin("Test pin 4 high", fd, pin+1, HIGH); | |||
digitalWrite(pinBase + pin, LOW); | |||
testPin("Test pin 3 low", fd, pin , LOW); | |||
testPin("Test pin 4 high", fd, pin+1, HIGH); | |||
ShowAll(); | |||
digitalWrite(pinBase + pin, HIGH); | |||
testPin("Test pin 3 high", fd, pin , HIGH); | |||
testPin("Test pin 4 high", fd, pin+1, HIGH); | |||
ShowAll(); | |||
printf("\nwiringPiI2CReadReg8:\n"); | |||
int i2cin, expect; | |||
i2cin = wiringPiI2CReadReg8(fd, 0x00); | |||
expect = ShowAll(); | |||
CheckSame("all low wiringPiI2CReadReg8", i2cin, expect); | |||
i2cin = wiringPiI2CReadReg8(fd, 0xFF); | |||
expect =ShowAll(); | |||
CheckSame("all high wiringPiI2CReadReg8", i2cin, expect); | |||
printf("\nwiringPiI2CReadBlockData:\n"); | |||
uint8_t value; | |||
int result; | |||
value = 0xFF; | |||
result = wiringPiI2CReadBlockData(fd, 0x00, &value, 1); | |||
CheckSame("wiringPiI2CReadBlockData result", result, 1); | |||
expect = ShowAll(); | |||
CheckSame("all high wiringPiI2CReadBlockData", value, expect); | |||
printf("\n"); | |||
value = 0x00; | |||
result = wiringPiI2CReadBlockData(fd, 0xFF, &value, 1); | |||
CheckSame("wiringPiI2CReadBlockData result", result, 1); | |||
expect = ShowAll(); | |||
CheckSame("all low wiringPiI2CReadBlockData", value, expect); | |||
return UnitTestState(); | |||
} | |||