add driver stub for Sensirion SEN5x PM sensor

1 files changed, 51 insertions, 0 deletions

diff --git a/src/driver/sen5x.cc b/src/driver/sen5x.cc
new file mode 100644
index 0000000..2a5d6b8
--- /dev/null
+++ b/src/driver/sen5x.cc
@@ -0,0 +1,51 @@
+/*
+ * Copyright 2021 Daniel Friesel
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#include "arch.h"
+#include "driver/sen5x.h"
+#if defined(CONFIG_meta_driver_hardware_i2c)
+#include "driver/i2c.h"
+#elif defined(CONFIG_driver_softi2c)
+#include "driver/soft_i2c.h"
+#endif
+
+void SEN5x::start()
+{
+	txbuf[0] = 0x00;
+	txbuf[1] = 0x21;
+	i2c.xmit(address, 2, txbuf, 0, rxbuf);
+}
+
+void SEN5x::stop()
+{
+	txbuf[0] = 0x01;
+	txbuf[1] = 0x04;
+	i2c.xmit(address, 2, txbuf, 0, rxbuf);
+}
+
+bool SEN5x::read()
+{
+	txbuf[0] = 0x03;
+	txbuf[1] = 0xc4;
+
+	if (i2c.xmit(address, 2, txbuf, 0, rxbuf)) {
+		return false;
+	}
+	arch.delay_ms(20);
+	if (i2c.xmit(address, 0, txbuf, 24, rxbuf)) {
+		return false;
+	}
+	pm1 = (rxbuf[0] << 8) + rxbuf[1];
+	pm2_5 = (rxbuf[3] << 8) + rxbuf[4];
+	pm4 = (rxbuf[6] << 8) + rxbuf[7];
+	pm10 = (rxbuf[9] << 8) + rxbuf[10];
+	humidity = (rxbuf[12] << 8) + rxbuf[13];
+	temperature = (rxbuf[15] << 8) + rxbuf[16];
+	voc = (rxbuf[18] << 8) + rxbuf[19];
+	nox = (rxbuf[21] << 8) + rxbuf[22];
+	return true;
+}
+
+SEN5x sen5x;