T48 EMMC ISP error 27 t48, isp, emmc

martian

Hi!
I've been trying to dump an EMMC chip using EMMC_ISP 2022 VER 1.0 adapter.
Every time I try to identify the chip I get error 27.
Same thing happens both in VCC3.3/VCCQ1.8, VCC1.8/VCCQ1.8 and VCC3.3/VCC3.3 modes.
I've tried both internal and external power.


To rule out a problem with the target board I tried connecting to a plain SD card in 1bit mode - same problem, error 27.


Can you help me, please?

martian

I'm using the latest version of the software - 12.45.

martian

So I've taken closer look at the adaptor and I see that there's a 1 ohm pull up on the CMD mosfet, that seems very high. The pull down also doesn't seem to get disabled for reading.
Is this board meant for some high power MMC that can drive that mosfet low? Otherwise I'm not sure I understand how this can ever work.

admin

回复 3# martian


   PULL UP CMD R is 10K

martian

回复 4# admin


   Oh, you're right! I measured it and it is in fact 10kOhm, the marking is just "010" which is usually 1 ohm.Do you know why I might be getting error 27 then?