1 files changed, 61 insertions, 0 deletions
diff --git a/fw/transpose.c b/fw/transpose.c
new file mode 100644
index 0000000..1c5f982
--- /dev/null
+++ b/fw/transpose.c
@@ -0,0 +1,61 @@
+
+#include <unistd.h>
+#include <string.h>
+
+#include "transpose.h"
+
+void transpose_data(volatile uint8_t *rx_buf, volatile struct framebuf *out_fb) {
+    memset((uint8_t *)out_fb, 0, sizeof(*out_fb));
+    struct data_format *rxp = (struct data_format *)rx_buf;
+    for (int bit=0; bit<8; bit++) { /* bits */
+        uint32_t bit_mask = 1U<<bit;
+        volatile uint32_t *frame_data = out_fb->frame[bit+2].data;
+        uint8_t *start_inp = rxp->high;
+        for (volatile uint32_t *outp=frame_data; outp<frame_data+8; outp++) { /* segments */
+            uint32_t acc = 0;
+            uint8_t *inp = start_inp++;
+            for (int digit=0; digit<32; digit++) {
+                acc |= (*inp & bit_mask) >> bit << digit;
+                inp += sizeof(struct data_format);
+            }
+            *outp = acc;
+        }
+    }
+    for (int bit=0; bit<2; bit++) { /* bits */
+        volatile uint32_t *frame_data = out_fb->frame[bit].data;
+        uint16_t *inp = &rxp->low;
+        for (int seg=0; seg<8; seg++) { /* segments */
+            uint32_t mask = 1 << bit << (seg*2);
+            uint32_t acc = 0;
+            for (int digit=0; digit<32; digit++) {
+                acc |= (*inp & mask) >> bit >> seg << digit;
+                inp += sizeof(struct data_format)/sizeof(uint16_t);
+            }
+            frame_data[seg] = acc;
+        }
+    }
+}
+
+
+void untranspose_data(struct framebuf *fb, uint8_t *txbuf) {
+    memset(txbuf, 0, sizeof(*fb));
+
+    struct data_format *tx = (struct data_format *) txbuf;
+
+    for (size_t i=0; i<32; i++) { /* digit */
+        for (size_t j=0; j<8; j++) { /* segment */
+            for (size_t k=0; k<8; k++) { /* bit */
+                tx[i].high[j] |= (fb->frame[k+2].data[j] & (1<<i)) ? (1<<k) : 0;
+            }
+        }
+    }
+
+    for (size_t i=0; i<32; i++) { /* digit */
+        for (size_t j=0; j<8; j++) { /* segment */
+            for (size_t k=0; k<2; k++) { /* bit */
+                tx[i].low |= (fb->frame[k].data[j] & (1<<i)) ? (1<<k<<(j*2)) : 0;
+            }
+        }
+    }
+}
+