diff --git a/ports/arm/platforms/dm36x/dm36x-io.h b/ports/arm/platforms/dm36x/dm36x-io.h
index fe0b434..03d0ab9 100644
--- a/ports/arm/platforms/dm36x/dm36x-io.h
+++ b/ports/arm/platforms/dm36x/dm36x-io.h
@@ -158,6 +158,14 @@
 #define DM36X_PLLC_PLLDIV9       0x174
 
 
+/** Power and sleep controller registers */
+#define DM36X_PSC_BASE          0x01C41000 /* PSC registers */
+#define DM36X_PSC_PTCMD         0x120
+#define DM36X_PSC_PTSTAT        0x128
+#define DM36X_PSC_MDSTAT_I2C    0x800 + (18 * 4)
+#define DM36X_PSC_MDCTL_I2C     0xA00 + (18 * 4)
+
+
 /** I2C registers */
 #define DM36X_I2C_BASE          0x01C21000 /* I2C */
 #define DM36X_I2C_ICOAR         0x00