Differences

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--- x68000:writing_drivers [2014/07/11 00:47] – eidis
+++ x68000:writing_drivers [2014/07/11 00:56] – eidis
@@ Line 13: / Line 13: @@
 **Note :** the following contains very hard stuff ! I might be confusing sometimes, sorry in advance. Don't hesitate to ask for help if you do not understand something. Thank you.
 **Terminology :**
@@ Line 21: / Line 20: @@
   * Char : 1 character = 1 byte
   * All data types are CPU specific : M68K family. So, byte ordering is always "Big Endian" and a pointer is 32 bits (long).
 ====== Compilation flags, libraries and startup code ======
@@ Line 49: / Line 47: @@
   * __next header__ (long) : A single .SYS or .X file may contains more than one drivers, so this a pointer to the next driver header within this file. Set this member to -1 (0xFFFFFFFF) if this driver entry is the last one in the chain.
   * __attributes__ (word): This 16 bits (1 word) member are flags that give informations about the driver behavior. Valid flags are :
     * 0x8000 : Character device driver (any driver that'll **NOT** talk to storage device, generally a disk containing a FAT filesystem). Unset this for a block device driver.
@@ Line 59: / Line 58: @@
     * 0x0002 : STDOUT device. The driver will redefine the stdout, for example : screen, serial output, printers,...
     * 0x0001 : STDIN device. The driver will redefine the stdin : keyboard or serial input.
   * __strategy routine (long)__: A pointer to the very first routine the kernel will execute ! This will initiate the driver loading.
   * __interrupt routine (long)__: A pointer to a routine that will perform the communication between the kernel and the device.
   * __driver name (8 chars)__: An unique identifier, also used by userspace application when executing IOCTL commands.
@@ Line 415: / Line 417: @@
-BIOS Parameter Block (BPB)
+====== BIOS Parameter Block (BPB) ======
 I will not explain this structure as there is plenty of informations about it on the internet.
 Starting from wikipedia : http://en.wikipedia.org/wiki/BIOS_parameter_block
 Just read everything you can about FAT12 and FAT16. 95% of these also apply to Human68k.
-Most of difference is the byte ordering, which is big endian instead of little endian. The structure is also a bit different. From my ddk.h file :
-Code: [Select]
+Most of difference is the byte ordering, which is big endian instead of little endian. The structure is also a bit different.
+From my ddk.h file :
+<file>
 struct bpb {
   UWORD bpb_nbyte;	/* Bytes per sector */
@@ Line 433: / Line 441: @@
   ULONG bpb_huge;	/* Size in sectors if bpb_nsize == 0 (32 bits) */
 };
+</file>
 See ? Only the "number of FAT" and "number of reserved sectors" members are swapped.