eMMC upgrade in Canon camcorder - Page 1
Forum section: electronics / general

author: NickyYTSRB
author_rank: Newbie
timestamp: September 23, 2018, 01:17:45 pm
content: Can i just replace Samsung KLM8G1GEAC-B031 with for example 32G chip? Is there any needed data on emmc for camcorder to work correctly like partition table or something? I removed the module from camcorder and it still works so firmware is not on emmc. My idea is to order 32G or 64G chip and replace it. Will it work?

author: dgtl
author_rank: Regular Contributor
timestamp: September 23, 2018, 01:33:56 pm
content: EMMC has hw boot partition (or two), some configuration bytes and the large user partition. If the device does not boot from emmc, it is quite probable, that they do not care about the boot partition and the configuration (most of it handles the boot partition usage and boot modes). Changing these settings and boot partitions is a bit difficult, typical usb sd-card readers do not expose this.The hw user partition has the typical partition table and data partitions within. The partition table can be either the old DOS partition table or GPT. If the partition table is of the wrong type, you may need to repartition it. Then the file system may need to be reformatted to one of the supported types. It is quite possible that the eMMC will work in a usb SD card reader when you wire it up (only first 1 or 4 data pins, though), so you may need to connect it up this way and this exposes you the full user partiton.

author: NickyYTSRB
author_rank: Newbie
timestamp: September 23, 2018, 01:44:47 pm
content: Well camcorder has option to initialize builtin memory so i guess that it does formatting at same time. So as first step should i try to guess the pinout of that flat flex connector and try to read it as sdcard?

author: dgtl
author_rank: Regular Contributor
timestamp: September 23, 2018, 01:58:04 pm
content: Reading it with sd-card reader should work (unless the reader is doing something stupid to limit itself to sd card only). The SD and eMMC are both superset of old MMC protocol, so the reader should be able to fall back to older MMC protocol and still work. I havent tried it myself though as I develop new devices and then the eMMC has to be initialized via the device cpu in circuit anyway. But there are records of doing it, iehttps://www.blackhat.com/docs/us-17/wednesday/us-17-Etemadieh-Hacking-Hardware-With-A-$10-SD-Card-Reader.pdfYou should be able to use only the 1-bit mode, so only DAT0, CMD, CLK, pwr and gnd wires.The initialization of the memory may not be enough as it maybe does not create partition table or format partitions. You can try and if it fails, then do it manually. Anyway having a dump of the old chip would be nice as then you know what you need to do.And then is still the question if the device uses the full card size or is forced to some predefined size in fw or reads out the chip id and does not want to support other chips. For no reason.

author: NickyYTSRB
author_rank: Newbie
timestamp: September 23, 2018, 08:29:17 pm
content: Well i have stupid question. Do all physically same emmcs have same pinouts?Edit: After searching for a while im thinking of buying KLMCG8GEAC-B031 and giving it a try but i can see KLMCG8GEAC-B001 on the web, what is the difference? I can find KLMCG8GEAC-B001 on the web that look like original part but KLMCG8GEAC-B031 does not have Samsung on it. Should i buythis B001orthis B031?

author: thm_w
author_rank: Super Contributor
timestamp: September 24, 2018, 10:06:35 pm
content: B001 is EMMC v4.5 and B031 is v5.0It says they are backwards compatible, but if that board has B031 already on it, I would tend to go with the same version in case they are using any new features.ftp://62.16.43.145/Datasheets/EMMC_KLMxGxxEMx-B031(eMMC5.0%201xnm%20based%20e_MMC)1.0.pdfhttps://wenku.baidu.com/view/1223470c482fb4daa58d4bac.html?re=viewhttps://www.datalight.com/solutions/technologies/emmc/emmc-feature-comparison-by-version

author: langwadt
author_rank: Super Contributor
timestamp: September 24, 2018, 11:03:16 pm
content: you could get adventurous and make a board with an SD card slot, the interface is very similar