add fat layout
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		| @@ -442,15 +442,35 @@ fat12_boot_sector_t const _boot_sect = | ||||
|     .fs_type            = "FAT12   " | ||||
| }; | ||||
|  | ||||
| /* 0  ______________ | ||||
|  *   | Boot Sector |  Fat copies = 1, Fat size = 7 | ||||
|  *   |_____________|  Root Dir = 16*8 (4KB), sector per cluster = 1 | ||||
|  * 1 |    FAT0     | | ||||
|  * . |             | | ||||
|  * . |  ( 7x512 )  | | ||||
|  * 7 |_____________| | ||||
|  * 8 |   Root Dir  | | ||||
|  * . |             | | ||||
|  * . |  ( 8x512 )  | | ||||
|  * 15|_____________| | ||||
|  * 16|             | | ||||
|  * . |             | | ||||
|  * . |             | | ||||
|  * . |    Data     | | ||||
|  * . |             | | ||||
|  * . |             | | ||||
|  *   |_____________| | ||||
|  */ | ||||
|  | ||||
| static inline bool fat12_formatted(void) | ||||
| { | ||||
|   const uint8_t* boot_sect = (uint8_t* ) lba2addr(0); | ||||
|   return (boot_sect[510] == 0x55) && (boot_sect[511] == 0xAA); | ||||
| } | ||||
|  | ||||
| static void fat12_write_cluster(uint16_t cluster_num, uint8_t const* buf, uint32_t bufsize) | ||||
| static void fat12_write_sector(uint32_t lba, uint8_t const* buf, uint32_t bufsize) | ||||
| { | ||||
|   uint32_t addr = lba2addr(cluster_num*8); | ||||
|   uint32_t addr = lba2addr(lba); | ||||
|  | ||||
|   nrf_nvmc_page_erase( addr ); | ||||
|   nrf_nvmc_write_words(addr, (uint32_t const*) buf, bufsize/4); | ||||
| @@ -470,7 +490,7 @@ static void fat12_mkfs(void) | ||||
|   memcpy(_page_cached+MSC_FLASH_BLOCK_SIZE, "\xF8\xFF\xFF\xFF\x0F\x00", 6); | ||||
|  | ||||
|   // Erase and Write first cluster. | ||||
|   fat12_write_cluster(0, _page_cached, FL_PAGE_SIZE); | ||||
|   fat12_write_sector(0, _page_cached, FL_PAGE_SIZE); | ||||
|  | ||||
|   //------------- Root Directory cluster -------------// | ||||
|   uint8_t const readme_contents[] = "Adafruit Feather nRF52840"; | ||||
| @@ -508,14 +528,14 @@ static void fat12_mkfs(void) | ||||
|   }; | ||||
|  | ||||
|   // Erase and Write cluster. | ||||
|   fat12_write_cluster(1, _page_cached, FL_PAGE_SIZE); | ||||
|   fat12_write_sector(8, _page_cached, FL_PAGE_SIZE); | ||||
|  | ||||
|   //------------- Readme Content cluster -------------// | ||||
|   memclr_(_page_cached, sizeof(_page_cached)); | ||||
|   memcpy(_page_cached, readme_contents, sizeof(readme_contents)-1); | ||||
|  | ||||
|   // Erase and Write cluster. | ||||
|   fat12_write_cluster(2, _page_cached, FL_PAGE_SIZE); | ||||
|   fat12_write_sector(16, _page_cached, FL_PAGE_SIZE); | ||||
| } | ||||
|  | ||||
| #endif | ||||
|   | ||||
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