Some info about building bugs on AMBIKA

Discontinued products Ambika
#1

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.

Greets

Andre’

#2

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:

#3

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

#4

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.

#5

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

#6

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

#7

-deleted(ish)-

#8

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?

#9

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:

#10

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).

#11

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.