diff --git a/spi_interface_radiant/spi_interface.v b/spi_interface_radiant/spi_interface.sv
similarity index 99%
rename from spi_interface_radiant/spi_interface.v
rename to spi_interface_radiant/spi_interface.sv
index 1820f88..b118ef6 100644
--- a/spi_interface_radiant/spi_interface.v
+++ b/spi_interface_radiant/spi_interface.sv
@@ -30,16 +30,12 @@ interface spi_interface_ports (input clk);
   logic spi1_sck_io;		// Clock for SPI-Slave
   
   // MODPORT form BUS perspective (internal)
-  // modport output from BUS (internal)
-  modport BUS (output sb_clk_i, sb_stb_i, sb_wr_i, sb_adr_i, sb_dat_i, spi1_miso_io);
-  // modport input to BUS (internal)
-  modport BUS (input sb_dat_o, sb_ack_o, spi1_mosi_io, spi1_mcs_n_o, spi_sck_io);
+  // modport input and output from BUS (internal)
+  modport BUS (output sb_clk_i, sb_stb_i, sb_wr_i, sb_adr_i, sb_dat_i, spi1_miso_io, input sb_dat_o, sb_ack_o, spi1_mosi_io, spi1_mcs_n_o, spi1_sck_io);
   
   // MODPORT from SPI perspective (external)
-  // modport output from SPI (external)
-  modport SPI (output spi1_miso_io);
-  // modport input to SPI (external)
-  modport SPI (input spi1_mosi_io, spi1_mcs_n_o, spi_sck_io);
+  // modport input and output from SPI (external)
+  modport SPI (output spi1_miso_io, input spi1_mosi_io, spi1_mcs_n_o, spi1_sck_io);
 
 endinterface