aboutsummaryrefslogtreecommitdiffstats
path: root/control_lib/sd_spi_wb.v
diff options
context:
space:
mode:
authorjcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5>2008-09-08 01:00:12 +0000
committerjcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5>2008-09-08 01:00:12 +0000
commit61f2f0214c5999ea42a368a4fc99f03d8eb28d1e (patch)
treee7e24a9adc05ff1422fe3ada9926a51634741b47 /control_lib/sd_spi_wb.v
downloaduhd-61f2f0214c5999ea42a368a4fc99f03d8eb28d1e.tar.gz
uhd-61f2f0214c5999ea42a368a4fc99f03d8eb28d1e.tar.bz2
uhd-61f2f0214c5999ea42a368a4fc99f03d8eb28d1e.zip
Merged r9433:9527 from features/gr-usrp2 into trunk. Adds usrp2 and gr-usrp2 top-level components. Trunk passes distcheck with mb-gcc installed, but currently not without them. The key issue is that when mb-gcc is not installed, the build system skips over the usrp2/firmware directory, and the firmware include files don't get put into the dist tarball. But we can't do the usual DIST_SUBDIRS method as the firmware is a subpackage.
git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@9528 221aa14e-8319-0410-a670-987f0aec2ac5
Diffstat (limited to 'control_lib/sd_spi_wb.v')
-rw-r--r--control_lib/sd_spi_wb.v66
1 files changed, 66 insertions, 0 deletions
diff --git a/control_lib/sd_spi_wb.v b/control_lib/sd_spi_wb.v
new file mode 100644
index 000000000..53036d363
--- /dev/null
+++ b/control_lib/sd_spi_wb.v
@@ -0,0 +1,66 @@
+
+// Wishbone module for spi communications with an SD Card
+// The programming interface is simple --
+// Write the desired clock divider to address 1 (should be 1 or higher)
+// Status is in address 0. A 1 indicates the last transaction is done and it is safe to
+// send another
+// Writing a byte to address 2 sends that byte over SPI. When it is done,
+// status (addr 0) goes high again, and the received byte can be read from address 3.
+
+module sd_spi_wb
+ (input clk,
+ input rst,
+
+ // SD Card interface
+ output sd_clk,
+ output sd_csn,
+ output sd_mosi,
+ input sd_miso,
+
+ input wb_cyc_i,
+ input wb_stb_i,
+ input wb_we_i,
+ input [1:0] wb_adr_i,
+ input [7:0] wb_dat_i,
+ output reg [7:0] wb_dat_o,
+ output reg wb_ack_o);
+
+ localparam ADDR_STATUS = 0;
+ localparam ADDR_CLKDIV = 1;
+ localparam ADDR_WRITE = 2;
+ localparam ADDR_READ = 3;
+
+ wire [7:0] status, rcv_dat;
+ reg [7:0] clkdiv;
+ wire ready;
+ reg ack_d1;
+ always @(posedge clk)
+ if(rst) ack_d1 <= 0;
+ else ack_d1 <= wb_ack_o;
+
+ always @(posedge clk)
+ if(rst) wb_ack_o <= 0;
+ else wb_ack_o <= wb_cyc_i & wb_stb_i & ~ack_d1;
+
+ always @(posedge clk)
+ case(wb_adr_i)
+ ADDR_STATUS : wb_dat_o <= {7'd0,ready};
+ ADDR_CLKDIV : wb_dat_o <= clkdiv;
+ ADDR_READ : wb_dat_o <= rcv_dat;
+ default : wb_dat_o <= 0;
+ endcase // case(wb_adr_i)
+
+ always @(posedge clk)
+ if(wb_we_i & wb_stb_i & wb_cyc_i & wb_ack_o)
+ case(wb_adr_i)
+ ADDR_CLKDIV : clkdiv <= wb_dat_i;
+ endcase // case(wb_adr_i)
+
+ wire go = wb_we_i & wb_stb_i & wb_cyc_i & wb_ack_o & (wb_adr_i == ADDR_WRITE);
+
+ sd_spi sd_spi(.clk(clk),.rst(rst),
+ .sd_clk(sd_clk),.sd_mosi(sd_mosi),.sd_miso(sd_miso),
+ .clk_div(clkdiv),.send_dat(wb_dat_i),.rcv_dat(rcv_dat),
+ .go(go),.ready(ready) );
+
+endmodule // sd_spi_wb