\n
![\"raspi-eeprom\"](\"http:\/\/www.pinewell.jp\/wordpress\/wp-content\/uploads\/2014\/01\/raspi-eeprom-2-2.png\")
<\/a>\nSCL\u3068SDA\u3092\u7e4b\u304e1k\u03a9\u3067\u30d7\u30eb\u30a2\u30c3\u30d7\u3002\u96fb\u6e90\u306f3.3V\u3002
\nraspi\u3067\u306eEEPROM\u8aad\u307f\u66f8\u304d\u30bd\u30d5\u30c8\u306f\u4ee5\u4e0b\u3088\u308a\u3002
\nhttps:\/\/github.com\/dgallot\/i2c-tools\/tree\/master\/eepromer\/<\/a>
\neeprom.c\u3092\u30c0\u30a6\u30f3\u30ed\u30fc\u30c9\u3057\u3066\u3001EEPROM\u306e\u30b5\u30a4\u30ba\u306b\u3042\u308f\u305b\u3066\u9069\u5b9c\u7de8\u96c6\u3002
\n24LC01\u306a\u3089 DEFAULT_NUM_PAGES \u3092 8,BYTES_PER_PAGE \u3092128,MAX_BYTES \u30928 \u306b\u5909\u66f4\u3002
\nraspi\u3067\u306ei2c\u30c7\u30d0\u30a4\u30b9\u306e\u6709\u52b9\u5316\u306f\u691c\u7d22\u3059\u308c\u3070\u3067\u3066\u304f\u308b\u3002
\nhttp:\/\/www.gallot.be\/?p=180<\/a> \u3053\u306e\u30da\u30fc\u30b8\u3092\u53c2\u8003\u306b\u3057\u305f\u304c\u3001\u30ef\u30b7\u306e\u74b0\u5883\u3067\u306f \/dev\/i2c-1 \u3067\u3042\u308b\u5fc5\u8981\u304c\u3042\u3063\u305f\u3002<\/p>\n
#i2cdetect -y -a 1\n 0 1 2 3 4 5 6 7 8 9 a b c d e f \n00: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- \n10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- \n20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- \n30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- \n40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- \n50: 50 51 52 53 54 55 56 57 -- -- -- -- -- -- -- -- \n60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- \n70: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- <\/pre>\n\u306750~\u306bEEPROM\u304c\u8a8d\u8b58\u3055\u308c\u3066\u3044\u308b\u3068\u8a00\u3046\u3053\u3068\u3060\u3068\u601d\u3046\u3002<\/p>\n
\u8aad\u307f\u51fa\u3057\u3002-p 2\u306f1\u30da\u30fc\u30b8128bytex2\u3067256byte\u5206\u3002 -f \u3067 \u8aad\u307f\u51fa\u3057\u5148\u30d5\u30a1\u30a4\u30eb\u540d\u3002<\/p>\n
# .\/eeprom -p 2 -f EDID.bin\nbase-address of eeproms : 0x50\nnumber of pages to read : 2 (0x50 .. 0x51)\nfile opened for writing : EDID.bin\n on filedescriptor : 3\ni2c-devicenode is : \/dev\/i2c-1\n on filedescriptor : 4\nRead 8 bytes from eeprom at 0x50, offset 00000000\n---\u5272\u611b---<\/pre>\n\u66f8\u304d\u8fbc\u307f\u3002<\/p>\n
#.\/eeprom -w -p 2 -f EDID.bin \nbase-address of eeproms : 0x50\nnumber of pages to read : 2 (0x50 .. 0x51)\nfile opened for reading : EDID_CDU2150A_256byte.bin\n on filedescriptor : 3\ni2c-devicenode is : \/dev\/i2c-1\n on filedescriptor : 4\n\n**WARNING**\n - You have chosen to WRITE to this eeprom.\n Make sure that this tiny chip is *NOT* vital to the\n operation of your computer as you can easily corrupt\n the configuration memory of your SDRAM-memory-module,\n your IBM ThinkPad or whatnot...! Fixing these errors can be\n a time-consuming and very costly process!\n\nThings to consider:\n - You can have more than one i2c-bus, check in \/proc\/bus\/i2c\n and specify the correct one with -d\n right now you have chosen to use '\/dev\/i2c-1'\n - A eeprom can occupy several i2c-addresses (one per page)\n so please make sure that there is no vital eeprom in your computer\n sitting at addresses between 0x50 and 0x51\nEnter 'yes' to continue:yes\nWrote 8 bytes to eeprom at 0x50, offset 00000000\n...... acked \nWrote 8 bytes to eeprom at 0x50, offset 00000008\n...... acked \n\u5272\u611b<\/pre>\n\u66f8\u304d\u8fbc\u307e\u308c\u305f\u30c7\u30fc\u30bf\u306f\u304d\u3061\u3093\u3068\u8aad\u307f\u51fa\u3057\u3067\u304d\u308b\u304b\u78ba\u8a8d\u3057\u3066\u5b9f\u969b\u306boverride\u30b1\u30fc\u30d6\u30eb\u306b\u4ed8\u3051\u3066\u307f\u308b\u3002
\n\u30c9\u30ad\u30c9\u30ad\u3057\u306a\u304c\u3089T221\u63a5\u7d9aPC\u306e\u96fb\u6e90\u3092\u3044\u308c\u308b\u3068\u3042\u3063\u3055\u308a\u6620\u308b\u3002\u6210\u529f\u3002
\nEEPROM\u3082\u624b\u306b\u5165\u3063\u305f\u3057\u30c7\u30fc\u30bf\u306e\u66f8\u304d\u8fbc\u307f\u3082\u78ba\u8a8d\u3067\u304d\u305f\u306e\u3067\u3042\u3068\u306fDVI\u30b1\u30fc\u30d6\u30eb\u3092
\n\u30cf\u30fc\u30c9\u30aa\u30d5\u3067\u8cb7\u3063\u3066\u6765\u3066ROM\u3092\u4e57\u3063\u3051\u308c\u3070EDID\u4e57\u3063\u53d6\u308a\u30b1\u30fc\u30d6\u30eb\u306e\u51fa\u6765\u4e0a\u304c\u308a\u3001\u3068\u3002<\/p>\nEDID\u30c7\u30fc\u30bf\u306e\u4f5c\u6210\u3082\u3081\u3093\u3069\u3046\u305d\u3046\u3060\u304c…..<\/p>\n
github\u3067\u516c\u958b\u3055\u308c\u3066\u3044\u308b\u3057\u3001\u591a\u5206\u5927\u4e08\u592b\u3060\u3068\u601d\u3046\u306e\u3067\u4ee5\u4e0b eeprom.c \u306e\u5168\u30bd\u30fc\u30b9\u3002<\/p>\n
\/*\nThis program is hereby placed into the public domain.\nOf course the program is provided without warranty of any kind.\n\nDownloaded from http:\/\/www.lm-sensors.org\/browser\/i2c-tools\/trunk\/eepromer\/eeprom.c\n\n*\/\n#include <sys\/ioctl.h>\n#include <errno.h>\n#include <stdio.h>\n#include <stdlib.h>\n#include <unistd.h>\n#include <fcntl.h>\n#include <string.h>\n#include <time.h>\n#include <linux\/i2c-dev.h>\n\n\/*\n this program can read 24C16 (and probably smaller ones, too)\n I wrote it as a quick and dirty hack because my satellite receiver\n hung again... so I had to reprogram the eeprom where is stores it's\n settings.\n *\/\n\n#define DEFAULT_I2C_BUS \"\/dev\/i2c-0\"\n#define DEFAULT_EEPROM_ADDR 0x50 \/* the 24C16 sits on i2c address 0x50 *\/\n#define DEFAULT_NUM_PAGES 8 \/* we default to a 24C16 eeprom which has 8 pages *\/\n#define BYTES_PER_PAGE 256 \/* one eeprom page is 256 byte *\/\n#define MAX_BYTES 16 \/* max number of bytes to write in one chunk *\/\n \/* ... note: 24C02 and 24C01 only allow 8 bytes to be written in one chunk. *\n * if you are going to write 24C04,8,16 you can change this to 16 *\/\n\n\/* write len bytes (stored in buf) to eeprom at address addr, page-offset offset *\/\n\/* if len=0 (buf may be NULL in this case) you can reposition the eeprom's read-pointer *\/\n\/* return 0 on success, -1 on failure *\/\nint eeprom_write(int fd,\n\t\t unsigned int addr,\n\t\t unsigned int offset,\n\t\t unsigned char *buf,\n\t\t unsigned char len\n){\n\tstruct i2c_rdwr_ioctl_data msg_rdwr;\n\tstruct i2c_msg i2cmsg;\n\tint i;\n\tchar _buf[MAX_BYTES + 1];\n\n\tif(len>MAX_BYTES){\n\t fprintf(stderr,\"I can only write MAX_BYTES bytes at a time!\\n\");\n\t return -1;\n\t}\n\n\tif(len+offset >256){\n\t fprintf(stderr,\"Sorry, len(%d)+offset(%d) > 256 (page boundary)\\n\",\n\t\t\tlen,offset);\n\t return -1;\n\t}\n\n\t_buf[0]=offset; \/* _buf[0] is the offset into the eeprom page! *\/\n\tfor(i=0;i<len;i++) \/* copy buf[0..n] -> _buf[1..n+1] *\/\n\t _buf[1+i]=buf[i];\n\n\tmsg_rdwr.msgs = &i2cmsg;\n\tmsg_rdwr.nmsgs = 1;\n\n\ti2cmsg.addr = addr;\n\ti2cmsg.flags = 0;\n\ti2cmsg.len = 1+len;\n\ti2cmsg.buf = _buf;\n\n\tif((i=ioctl(fd,I2C_RDWR,&msg_rdwr))<0){\n\t if ( len > 0 ) {\n\t perror(\"ioctl()\");\n\t fprintf(stderr,\"ioctl returned %d\\n\",i);\n }\n\t return -1;\n\t}\n\n\tif(len>0)\n\t fprintf(stderr,\"Wrote %d bytes to eeprom at 0x%02x, offset %08x\\n\",\n\t\t len,addr,offset);\n\treturn 0;\n}\n\n\/* read len bytes stored in eeprom at address addr, offset offset in array buf *\/\n\/* return -1 on error, 0 on success *\/\nint eeprom_read(int fd,\n\t\t unsigned int addr,\n\t\t unsigned int offset,\n\t\t unsigned char *buf,\n\t\t unsigned char len\n){\n\tstruct i2c_rdwr_ioctl_data msg_rdwr;\n\tstruct i2c_msg i2cmsg;\n\tint i;\n\n\tif(len>MAX_BYTES){\n\t fprintf(stderr,\"I can only write MAX_BYTES bytes at a time!\\n\");\n\t return -1;\n\t}\n\n\tif(eeprom_write(fd,addr,offset,NULL,0)<0)\n\t return -1;\n\n\tmsg_rdwr.msgs = &i2cmsg;\n\tmsg_rdwr.nmsgs = 1;\n\n\ti2cmsg.addr = addr;\n\ti2cmsg.flags = I2C_M_RD;\n\ti2cmsg.len = len;\n\ti2cmsg.buf = buf;\n\n\tif((i=ioctl(fd,I2C_RDWR,&msg_rdwr))<0){\n\t perror(\"ioctl()\");\n\t fprintf(stderr,\"ioctl returned %d\\n\",i);\n\t return -1;\n\t}\n\n\tfprintf(stderr,\"Read %d bytes from eeprom at 0x%02x, offset %08x\\n\",\n\t\tlen,addr,offset);\n\n\treturn 0;\n}\n\n\n\nint main(int argc, char **argv){\n int i,j;\n\n \/* filedescriptor and name of device *\/\n int d; \n char *dn=DEFAULT_I2C_BUS;\n\n \/* filedescriptor and name of data file *\/\n int f=-1;\n char *fn=NULL;\n\n unsigned int addr=DEFAULT_EEPROM_ADDR;\n int rwmode=0;\n int pages=DEFAULT_NUM_PAGES;\n\n int force=0; \/* suppress warning on write! *\/\n int wait = 0;\n int acked = 0;\n \n while((i=getopt(argc,argv,\"d:a:p:wyf:h\"))>=0){\n\tswitch(i){\n\tcase 'h':\n\t fprintf(stderr,\"%s [-d dev] [-a adr] [-p pgs] [-w] [-y] [-f file]\\n\",argv[0]);\n\t fprintf(stderr,\"\\tdev: device, e.g. \/dev\/i2c-0 (def)\\n\");\n\t fprintf(stderr,\"\\tadr: base address of eeprom, eg 0xA0 (def)\\n\");\n\t fprintf(stderr,\"\\tpgs: number of pages to read, eg 8 (def)\\n\");\n\t fprintf(stderr,\"\\t-w : write to eeprom (default is reading!)\\n\");\n\t fprintf(stderr,\"\\t-y : suppress warning when writing (default is to warn!)\\n\");\n\t fprintf(stderr,\"\\t-f file: copy eeprom contents to\/from file\\n\");\n\t fprintf(stderr,\"\\t (default for read is test only; for write is all zeros)\\n\");\n\t fprintf(stderr,\"Note on pages\/addresses:\\n\");\n\t fprintf(stderr,\"\\teeproms with more than 256 byte appear as if they\\n\");\n\t fprintf(stderr,\"\\twere several eeproms with consecutive addresses on the bus\\n\");\n\t fprintf(stderr,\"\\tso we might as well address several separate eeproms with\\n\");\n\t fprintf(stderr,\"\\tincreasing addresses....\\n\\n\");\n\t exit(1);\n\t break;\n\tcase 'd':\n\t dn=optarg;\n\t break;\n\tcase 'a':\n\t if(sscanf(optarg,\"0x%x\",&addr)!=1){\n\t\tfprintf(stderr,\"Cannot parse '%s' as addrs., example: 0xa0\\n\",\n\t\t\toptarg);\n\t\texit(1);\n\t }\n\t break;\n\tcase 'p':\n\t if(sscanf(optarg,\"%d\",&pages)!=1){\n\t\tfprintf(stderr,\"Cannot parse '%s' as number of pages, example: 8\\n\",\n\t\t\toptarg);\n\t\texit(1);\n\t }\n\t break;\n\tcase 'w':\n\t rwmode++;\n\t break;\n\tcase 'f':\n\t fn=optarg;\n\t break;\n\tcase 'y':\n\t force++;\n\t break;\n\t}\n\n }\n \n fprintf(stderr,\"base-address of eeproms : 0x%02x\\n\",addr);\n fprintf(stderr,\"number of pages to read : %d (0x%02x .. 0x%02x)\\n\",\n\t\t pages,addr,addr+pages-1);\n\n if(fn){\n\tif(!rwmode) \/* if we are reading, *WRITE* to file *\/\n\t f=open(fn,O_WRONLY|O_CREAT,0666);\n\telse \/* if we are writing to eeprom, *READ* from file *\/\n\t f=open(fn,O_RDONLY);\n\tif(f<0){\n\t fprintf(stderr,\"Could not open data-file %s for reading or writing\\n\",fn);\n\t perror(fn);\n\t exit(1);\n\t}\n\tfprintf(stderr,\"file opened for %7s : %s\\n\",rwmode?\"reading\":\"writing\",fn);\n\tfprintf(stderr,\" on filedescriptor : %d\\n\",f);\n }\n\n if((d=open(dn,O_RDWR))<0){\n\tfprintf(stderr,\"Could not open i2c at %s\\n\",dn);\n\tperror(dn);\n\texit(1);\n }\n\n fprintf(stderr,\"i2c-devicenode is : %s\\n\",dn);\n fprintf(stderr,\" on filedescriptor : %d\\n\\n\",d);\n\n \/***\n *** I'm not the one to blame of you screw your computer!\n ***\/\n if(rwmode && ! force){\n\tunsigned char warnbuf[4];\n\tfprintf(stderr,\"**WARNING**\\n\");\n\tfprintf(stderr,\" - \\tYou have chosen to WRITE to this eeprom.\\n\");\n\tfprintf(stderr,\"\\tMake sure that this tiny chip is *NOT* vital to the\\n\");\n\tfprintf(stderr,\"\\toperation of your computer as you can easily corrupt\\n\");\n\tfprintf(stderr,\"\\tthe configuration memory of your SDRAM-memory-module,\\n\");\n\tfprintf(stderr,\"\\tyour IBM ThinkPad or whatnot...! Fixing these errors can be\\n\");\n\tfprintf(stderr,\"\\ta time-consuming and very costly process!\\n\\n\");\n\tfprintf(stderr,\"Things to consider:\\n\");\n\tfprintf(stderr,\" - \\tYou can have more than one i2c-bus, check in \/proc\/bus\/i2c\\n\");\n\tfprintf(stderr,\"\\tand specify the correct one with -d\\n\");\n\tfprintf(stderr,\"\\tright now you have chosen to use '%s'\\n\",dn);\n\tfprintf(stderr,\" - \\tA eeprom can occupy several i2c-addresses (one per page)\\n\");\n\tfprintf(stderr,\"\\tso please make sure that there is no vital eeprom in your computer\\n\");\n\tfprintf(stderr,\"\\tsitting at addresses between 0x%02x and 0x%02x\\n\",addr,addr+pages-1);\n\n\tfprintf(stderr,\"Enter 'yes' to continue:\");\n\tfflush(stderr);\n\tif(!fgets(warnbuf,sizeof(warnbuf),stdin)){\n\t fprintf(stderr,\"\\nCould not read confirmation from stdin!\\n\");\n\t exit(1);\n\t}\n\tif(strncmp(warnbuf,\"yes\",3)){\n\t fprintf(stderr,\"\\n** ABORTING WRITE! **, you did not answer 'yes'\\n\");\n\t exit(1);\n\t}\n }\n\n for(i=0;i<pages;i++){\n\tunsigned char buf[BYTES_PER_PAGE];\n\n\tif(rwmode){\n\n\t if(f>=0){\n\t\tj=read(f,buf,sizeof(buf));\n\t\tif(j<0){\n\t\t fprintf(stderr,\"Cannot read from file '%s'\\n\",fn);\n\t\t perror(fn);\n\t\t exit(1);\n\t\t}\n\t\tif(j!=sizeof(buf)){\n\t\t fprintf(stderr,\"File '%s' is too small, padding eeprom with zeroes\\n\",fn);\n\t\t while(j<sizeof(buf))\n\t\t\tbuf[j++]=0;\n\t\t}\n\t } else {\n\t\tfor(j=0;j<sizeof(buf);j++)\n\t\t buf[j]=0;\n\t }\n for(j=0;j<(BYTES_PER_PAGE\/MAX_BYTES);j++) {\n\t\tif(eeprom_write(d,addr+i,j*MAX_BYTES,buf+(j*MAX_BYTES),MAX_BYTES)<0)\n\t\t exit(1);\n fprintf(stderr,\".\");\n for ( wait = 0; wait < 10; wait ++ ) {\n acked = eeprom_write(d,addr+i,j*MAX_BYTES,NULL,0);\n if ( acked == 0 )\n break;\n fprintf(stderr,\".\");\n usleep( 100 );\n }\n if ( acked != 0 ) {\n fprintf(stderr,\"Ack of write operation timedout\");\n exit ( 1 );\n }\n fprintf(stderr,\" acked \\n\");\n }\n\t} else {\n for(j=0;j<(BYTES_PER_PAGE\/MAX_BYTES);j++)\n\t\tif(eeprom_read(d,addr+i,j*MAX_BYTES,buf+(j*MAX_BYTES),MAX_BYTES)<0)\n\t\t exit(1);\n\t}\n\n\n\tif(!rwmode && f>=0){\n\t j=write(f,buf,sizeof(buf));\n\t if(j!=sizeof(buf)){\n\t\tfprintf(stderr,\"Cannot write to file '%s'\\n\",fn);\n\t\tperror(fn);\n\t\texit(1);\n\t }\n\t}\n\n }\n\n if(f>=0)\n\tclose(f);\n\n close(d);\n\n exit(0);\n\n}<\/pre>\n","protected":false},"excerpt":{"rendered":"T221\u3084CDU2150A\u3092\u3088\u308a\u5feb\u9069\u306b\u4f7f\u3046\u306b\u3042\u305f\u308a\u306b\u554f\u984c\u3068\u306a\u308bEDID\u3002 \u67d0\u30aa\u30fc\u30af\u30b7\u30e7\u30f3\u306bEDID\u306eoverride\u3059\u308b\u5ef6\u9577\u30b1\u30fc\u30d6\u30eb\u3001ROM\u304c\u51fa\u54c1\u3055\u308c\u3066\u3044\u308b\u306e\u3060\u304c\u3044\u304b\u3093\u305b\u3093\u5b89\u304f\u306a\u3044\u3002 T221\u8cfc\u5165\u6642\u306boverride\u30b1\u30fc […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2,6],"tags":[],"class_list":["post-2469","post","type-post","status-publish","format-standard","hentry","category-2","category-6"],"views":5527,"_links":{"self":[{"href":"https:\/\/www.pinewell.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/2469","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.pinewell.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.pinewell.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.pinewell.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.pinewell.jp\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2469"}],"version-history":[{"count":0,"href":"https:\/\/www.pinewell.jp\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/2469\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.pinewell.jp\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2469"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.pinewell.jp\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2469"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.pinewell.jp\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2469"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}