diff --git a/Makefile b/Makefile
index 87845da..1ed21e0 100644
--- a/Makefile
+++ b/Makefile
@@ -23,7 +23,7 @@ ASFLAGS  = -march=rv32i -mabi=ilp32
 LD       = $(TARGET)-ld
 LDFLAGS  = -Tprogmem.lds -melf32lriscv
 CC       = $(TARGET)-gcc
-CFLAGS   = -march=rv32i -mabi=ilp32 -Wall -Wextra -pedantic
+CFLAGS   = -march=rv32i -mabi=ilp32 -Wall -Wextra -pedantic -DFREQ=$(FREQ_PLL)000000
 OBJCOPY  = $(TARGET)-objcopy
 
 .PHONY: all clean syntax time stat flash
diff --git a/progmem.c b/progmem.c
index d280bab..6a1d1da 100644
--- a/progmem.c
+++ b/progmem.c
@@ -6,7 +6,7 @@
 #define UART_DATA   *((volatile  int32_t *) 0x00020008)
 
 int main() {
-    UART_BAUD = 36000000 / 9600;
+    UART_BAUD = FREQ / 9600;
 
     for (;;) {
         int32_t c;