// set direction (out)
error = mraa_gpio_dir(m_clkPinCtx, MRAA_GPIO_OUT);
if (error != MRAA_SUCCESS) {
// set direction (out)
error = mraa_gpio_dir(m_clkPinCtx, MRAA_GPIO_OUT);
if (error != MRAA_SUCCESS) {
mraa_result_t error = MRAA_SUCCESS;
error = mraa_gpio_write (m_dataPinCtx, LOW);
usleep(100);
mraa_result_t error = MRAA_SUCCESS;
error = mraa_gpio_write (m_dataPinCtx, LOW);
usleep(100);
for(int idx = 0; idx < 4; idx++) {
error = mraa_gpio_write (m_dataPinCtx, HIGH);
error = mraa_gpio_write (m_dataPinCtx, LOW);
for(int idx = 0; idx < 4; idx++) {
error = mraa_gpio_write (m_dataPinCtx, HIGH);
error = mraa_gpio_write (m_dataPinCtx, LOW);