diff --git a/firmware/ice40-riscv/icE1usb/misc.h b/firmware/ice40-riscv/icE1usb/misc.h
index 36126da..6d90364 100644
--- a/firmware/ice40-riscv/icE1usb/misc.h
+++ b/firmware/ice40-riscv/icE1usb/misc.h
@@ -13,6 +13,12 @@
 enum pdm_chan {
 	PDM_CLK_LO	= 0,
 	PDM_CLK_HI	= 1,
+
+	/* icE1usb */
+	PDM_E1_RX0	= 2,
+	PDM_E1_RX1	= 3,
+
+	/* icE1usb-proto */
 	PDM_E1_N	= 2,
 	PDM_E1_P	= 3,
 	PDM_E1_CT	= 4,
@@ -20,4 +26,5 @@
 
 void pdm_set(int chan, bool enable, unsigned value, bool normalize);
 
+void e1_led_set(bool enable, uint8_t cfg);
 uint16_t e1_tick_read(void);