What is Reddit's opinion of DSD TECH SH-U09C5 USB to TTL UART Converter Cable with FTDI Chip Support 5V 3.3V 2.5V 1.8V TTL?

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I suppose they would probably follow that same practice on their cable tv boxes, hmm. That's good information.

I do have this coming in the mail on Wednesday: https://www.amazon.com/dp/B07WX2DSVB?psc=1&ref=ppx_yo2ov_dt_b_product_details

you think that will cut it for further testing?

For the adapter? That is how it is sold on Amazon here is the link: DSD TECH SH-U09C5 USB to TTL UART Converter Cable with FTDI Chip Support 5V 3.3V 2.5V 1.8V TTL https://www.amazon.com/dp/B07WX2DSVB/ref=cm_sw_r_cp_api_glt_i_JZXE4X4J9S0ZKBAER7ES.

I hit the same issue with my T420, never was able to revive it. My best guess is the EMMC chip that holds the firmware failed during the firmware write. There's some discussion in the win-raid forum post about replacing the chip, but that was outside my ability level.

Here's a list of resources I used trying to fix it though:

• https://www.win-raid.com/t3828f16-Problem-Dell-R-xd-iDRAC-BIOS-Recovery.html
• https://www.reddit.com/r/homelab/comments/960wx8/dell_r720_idrac_recovery/
• https://www.reddit.com/r/homelab/comments/9ldgre/running_custom_software_on_the_iloidrac/
• https://www.reddit.com/r/homelab/comments/abuc09/psa_read_this_before_you_upgrade_your_firmware_on/
• https://www.reddit.com/r/homelab/comments/a1ewte/bricked_an_r720_idrac_tonight_story_and_future/
• https://www.reddit.com/r/homelab/comments/ed3wkz/unbricking_a_r720xd/
• https://www.reddit.com/r/homelab/comments/a49b4y/r720_idrac_help/
• https://www.reddit.com/r/homelab/comments/bsou3n/dell_r520_idrac_7_swc0700_and_idrac8_prompt/
• http://wiki.loverpi.com/faq:sbc:libre-aml-s805x-serial-console-uboot

If you do decide to go down the path of trying to debug this, here's some of the tools I bought:

• https://www.amazon.com/gp/product/B07WX2DSVB
• https://www.amazon.com/gp/product/B01EV70C78

Here's where the UART Header and SW2 contacts are on the T420: https://imgur.com/a/mdGMsck

When triggering the SW2 terminal (the second pair from the top in the image above I believe) it's much easier to attach a wire to the server chassis ground and touch one of the contacts instead of trying to bridge the pair with tweezers or a wire.

Good luck if you try this!

Thank you for your reply.

Isn't the official one a bit overpriced (~30$)? I found this alternative, but I don't know if it will indeed work and which pins to connect. (If you wan to help, please read my other comment below. Thank you!).

EDIT: Nevermind, solved (see /u/OrYouCouldJustNot's comment below)

I found this other converter that supports 1.8V, however I am not sure how I shall connect it to the board.

Shall I just connect GND, RXD and TXD? What about the VCC pin, and voltage pins in the bottom left corner of the converter? I am looking specifically at this image: link.

EDIT: Nevermind, solved (see /u/OrYouCouldJustNot's comment below)

Thank you for the suggestion. Is there any chance that also this one will work? It's cheaper, but I don't know which pins I am supposed to connect, since there is both a VCC pin and voltage level (?) pins (on the bottom side).