Small optimizations

main.c

@@ -874,7 +874,7 @@ VNA_SHELL_FUNCTION(cmd_capture)
   // read pixel count at one time (PART*2 bytes required for read buffer)
   (void)argc;
   (void)argv;
-  int i, y;
+  int y;
 #ifdef TINYSA4  
 #if SPI_BUFFER_SIZE < (2*LCD_WIDTH)
 #error "Low size of spi_buffer for cmd_capture"
@@ -889,9 +889,7 @@ VNA_SHELL_FUNCTION(cmd_capture)
     // use uint16_t spi_buffer[2048] (defined in ili9341) for read buffer
     uint8_t *buf = (uint8_t *)spi_buffer;
     ili9341_read_memory(0, y, LCD_WIDTH, 2, 2 * LCD_WIDTH, spi_buffer);
-    for (i = 0; i < 4 * LCD_WIDTH; i++) {
+    streamWrite(shell_stream, (void*)buf, 2 * 2 * LCD_WIDTH);
-      streamPut(shell_stream, *buf++);
-    }
   }
 }
 

nanovna.h

@@ -896,8 +896,13 @@ typedef struct setting
   int decay;                      // KM_DECAY   < 1000000
   int attack;                     // KM_ATTACK  <   20000
 
-  int32_t  slider_position;
+#ifdef TINYSA4
-  int64_t slider_span;
+  int32_t slider_position;
+  int64_t  slider_span;
+#else
+  int32_t slider_position;
+  int32_t slider_span;
+#endif
 
   uint32_t rbw_x10;
   uint32_t vbw_x10;