Changes between Version 98 and Version 99 of library_stdio

Timestamp:

Jul 18, 2015, 9:19:15 PM (9 years ago)

Author:

alain

Comment:

--

library_stdio

@@ -365 +365 @@
  === 2) void '''giet_fbf_cma_init_buf'''( void* buf0_vbase , void* buf1_vbase , void* sts0_vaddr , void* sts1_vaddr ) ===
 This function initializes the chained buffer descriptors for the two source buffers and the frame buffer.
- * '''buf0_vbase''' is the first user buffer base address,
- * '''buf1_vbase''' is the second user buffer base address,
- * '''sts0_vaddr''' is the virtual address of the first buffer status,
- * '''sts1_vaddr''' is the virtual address of the second buffer status.
+The buf0 and buf1 user buffers must be large enough to store a complete image, and must be aligned on a 64 bytes boundary.
+The sts0 and sts1 user buffers contain just a Boolean, but they must be large enough to store 64 bytes, and must be aligned on a 64 bytes boundary.
+ * '''buf0_vbase''' : virtual address of the first data buffer.
+ * '''buf1_vbase''' : virtual address of  the second  data buffer,
+ * '''sts0_vaddr''' : virtual address of the first buffer status.
+ * '''sts1_vaddr''' : virtual address of the second buffer status.
 
  === 3) void '''giet_fbf_cma_start'''( unsigned int length ) ===
-This function initializes the chained buffer DMA controller (CMA) to transfer a stream of images from two user buffers to the frame buffer. It must be used in conjunction with the giet_fbf_cma_display() function. The chained buffer descriptors should have been initialized by the giet_fbf_cma_init_buf() function.
- * '''length''' is the buffer size (bytes). 
+This function activates the transfer of a stream of images from two user buffers to the frame buffer. It must be used in conjunction with the giet_fbf_cma_display() function. The chained buffer descriptors should have been initialized by the giet_fbf_cma_init_buf() function.
+ * '''length''' is the size of the image (bytes). 
 
  === 4) void '''giet_fbf_cma_display'''( unsigned int buffer ) ===