Some info about building bugs on AMBIKA

Hi all, i get here a buggy AMBIKA , short on 5 V. First i though that it was a wrong solder point but it wasn’t.
The guy had screw the nuts and bolts with so much power that the bolts make a short direct on the 5 V !
This means, i had to solder out the complete display.Mostly after solder out , the LCD is death .
Than i found a second thing. I order SD-Ram Cards from Reichelt. Platinum, 4 GB. costs 6€. Than i copy the firmware/patches on it. On the first try the AMBIKA found the patches. After switch off/on Ambika doesn’t found anything. Hmm, i do it a few times again with an old SD card 256Mb ram. works perfect.
Than i substitute the card with the platinum 4GB card. First it works, but after i switch AMBIKA of… wait a few seconds and switch it on again, Ambika doesn’t shows the patches.
I inform Olivier, he told me that some SD-Ram cards switch from SD to SDHC mode. This can be the bug.
He suggest me to use EMTEC 2 or 4 GB cards (from AMAZON)
Hope this info is helpfull.



Useful stuff. We’ve definitely had the SD quirk on here before. You really do need to get an old non-SDHC card for an easy life :slight_smile:

I own a Platinum SD Card, it does not work in Ambika, Sandisk is working well

Normal SD-Cards (not SDHC) with 2 GB max. are still available in every shop around because several digital cameras need them. They cost round about 7 Euro here.

Btw. I welcome the fact, that an ambika accepts old cards! I hate to know that I insert a memory card that will always be 99 % unused while smaller cards are collecting dust in the rear corner of my desktop drawer.

I’m also using a sandisk SDHC card and it seems to work perfectly fine.

It must relate to how quickly the card reacts upon bootup.


The mysterious problem is the following. Some of the SD cards that cause problems are SDHC but declare themselves as non-SDHC (byte-addressed rather than sector-addressed). The problem is either permanent (the card will never work) or random (the card mostly work but once in a while, it’ll declare itself as non-SDHC). I can provide logic analyzer traces to those who are interested in the problem. Maybe something power-supply related that causes the SD card’s firmware to fail to boot correctly?

FWIW, I had trouble with some SD cards in cameras as well as on my MBP as well. Maybe some are just a bit buggy. :wink:

My cheap Transcend card is often not found on startup, but if I take it out and insert it again it works fine (without powering down).

Hi, sometimes the LXR had this kind of problem. Help is, to solder a bigger cap 220 uf direct on 3,3 volt power supply. This i have read in the lxr forum.