diff --git a/hw/application_fpga/data/application_fpga_tk1.pcf b/hw/application_fpga/data/application_fpga_tk1.pcf
index efc5387..6bbb811 100644
--- a/hw/application_fpga/data/application_fpga_tk1.pcf
+++ b/hw/application_fpga/data/application_fpga_tk1.pcf
@@ -14,8 +14,8 @@
 # UART.
 set_io interface_rx 26
 set_io interface_tx 25
-set_io interface_ch552_cts 27
-set_io interface_fpga_cts 28
+set_io interface_ch552_cts 28
+set_io interface_fpga_cts 27
 
 
 # SPI master to flash memory.
diff --git a/hw/application_fpga/data/application_fpga_tk1_uwg30.pcf b/hw/application_fpga/data/application_fpga_tk1_uwg30.pcf
index 4163fa3..de8c4a5 100644
--- a/hw/application_fpga/data/application_fpga_tk1_uwg30.pcf
+++ b/hw/application_fpga/data/application_fpga_tk1_uwg30.pcf
@@ -15,8 +15,8 @@
 # UART.
 set_io interface_rx A2
 set_io interface_tx A1
-set_io interface_ch552_cts B3
-set_io interface_fpga_cts A4
+set_io interface_ch552_cts A4
+set_io interface_fpga_cts B3
 
 
 # SPI master to flash memory.
diff --git a/hw/usb_interface/ch552_fw/inc/gpio.h b/hw/usb_interface/ch552_fw/inc/gpio.h
index 1c710ea..e382570 100644
--- a/hw/usb_interface/ch552_fw/inc/gpio.h
+++ b/hw/usb_interface/ch552_fw/inc/gpio.h
@@ -9,8 +9,8 @@
 #define PIN_P1_4 0x10
 #define PIN_P1_5 0x20
 
-#define PIN_FPGA_CTS PIN_P1_4
-#define PIN_CH552_CTS PIN_P1_5
+#define PIN_FPGA_CTS PIN_P1_5
+#define PIN_CH552_CTS PIN_P1_4
 
 void gpio_set(uint8_t pin);
 void gpio_unset(uint8_t pin);