Move-E-Stor MkI

Forum for discussion of electronic television. Generally, stuff to do with CRTs and not using mechanical displays.

Re: Move-E-Stor MkI

Postby smeezekitty » Fri Dec 24, 2021 7:51 am

Any particular reason you're using jumpers to set the capacity instead of reading the card's C_SIZE register?
smeezekitty
Just nod and pretend you understand me
 
Posts: 217
Joined: Fri Jan 29, 2010 11:42 am
Location: USA

Re: Move-E-Stor MkI

Postby Steve Anderson » Fri Dec 24, 2021 11:48 am

Although I dabbled with SD cards a few years ago, I didn't become that familiar with their inner workings to an in-depth degree. Just enough to be able to read/write to them in a very basic manner. Now you've mentioned this I will investigate...along with anything else I may find along the way.

The initialization process is a minefield in itself!

Thus far I've been focusing on the creation of the WAV files, the A-D/D-A, the actual recording and playback processes. Especially the filtering required.

So thanks for the 'heads-up'.

Steve A.

P.S. I did consider using a spare IDE hard-drive, but they're big, heavy and power hungry in comparison, though I am very familiar with them.
User avatar
Steve Anderson
"Fester! Don't do that to 'Thing'"
 
Posts: 4854
Joined: Fri Mar 30, 2007 10:54 pm
Location: Bangkok, Thailand

Re: Move-E-Stor MkI

Postby smeezekitty » Fri Dec 24, 2021 6:00 pm

Steve Anderson wrote:Although I dabbled with SD cards a few years ago, I didn't become that familiar with their inner workings to an in-depth degree. Just enough to be able to read/write to them in a very basic manner. Now you've mentioned this I will investigate...along with anything else I may find along the way.

The initialization process is a minefield in itself!

Thus far I've been focusing on the creation of the WAV files, the A-D/D-A, the actual recording and playback processes. Especially the filtering required.

So thanks for the 'heads-up'.

Steve A.

P.S. I did consider using a spare IDE hard-drive, but they're big, heavy and power hungry in comparison, though I am very familiar with them.

Its true SD cards are a pain to work with but freeing up 3 microcontroller pins seems worthwhile.
I think pages 181-185 might be helpful for decoding the register https://academy.cba.mit.edu/classes/net ... /SD/SD.pdf

Have you looked into CF cards? They're small and light but I believe they speak IDE. Not quite as common as SDHC cards though
smeezekitty
Just nod and pretend you understand me
 
Posts: 217
Joined: Fri Jan 29, 2010 11:42 am
Location: USA

Re: Move-E-Stor MkI

Postby Steve Anderson » Sat Dec 25, 2021 1:18 pm

smeezekitty wrote:Have you looked into CF cards? They're small and light but I believe they speak IDE. Not quite as common as SDHC cards though


The major disadvantage with CF cards is the same as (E)IDE drives, (E)IDE hard drives have a 40-pin connector plus another 4-pin for power. A CF card has 50 pins including power. The I/O is primarily parallel rather than serial, so unless a micro with at least 60+ I/O pins is used you have to add a load of 'glue logic'. Also few people have smaller capacity CF cards kicking around in the bottom of a drawer somewhere. Plus the cost per GB is probably higher if buying new.

However, your C_SIZE suggestion yesterday made me invest several hours on reading up on SD cards, both to refresh my memory and generally getting to know them better. Worthwhile.

I'll concentrate on SDHC cards first (4 to 32GB), but there appears to me at the moment are large degree of commonality with the larger capacity SDXC cards, with just a few minor differences (Correct me if I'm wrong). I'm going to drop SDSC cards entirely. (2GB or less).

Another way to free up a few pins would be to change the UART baud rate through itself rather than jumpers, more anon.

Steve A.

P.S. Merry Christmas All...
User avatar
Steve Anderson
"Fester! Don't do that to 'Thing'"
 
Posts: 4854
Joined: Fri Mar 30, 2007 10:54 pm
Location: Bangkok, Thailand

Re: Move-E-Stor MkI

Postby Steve Anderson » Tue Dec 28, 2021 3:01 pm

Now that the Christmas Sherry has worn off I've had a good long review of this device.

First, we've all got access to a PC otherwise we could not partake in this forum. Second, any PC worth its salt has a USB port. Third, it probably has a vast amount of real estate for storage (disc space). There's always additional storage in the form of USB flash-drives or true external hard drives.

The original brief was to enable recordings to be made of NBTV waveforms that preserve and reproduce the video content with the DC component intact. A 'sound card' generally is incapable of doing so. This only is required on the video channel, not the audio.

So in effect this becomes a fast data logger with two channels, one DC-coupled, the other not so.

This is starting to sound a bit more realistic.

So what I've done here so far I'm going to put aside (yet keep) and follow on this thread of thinking. It should make the device somewhat simpler both in hardware and software. I did make a start on a device very similar in functionality some years ago, time for a review...

Steve A.
User avatar
Steve Anderson
"Fester! Don't do that to 'Thing'"
 
Posts: 4854
Joined: Fri Mar 30, 2007 10:54 pm
Location: Bangkok, Thailand

Re: Move-E-Stor MkI

Postby Steve Anderson » Fri Dec 31, 2021 1:35 pm

So, after some 'adjustment' here's the revision I intend to build. I've left PORT A (RA0-RA5) free such that a SD card interface could be added later.

Click the image for better resolution. Items in magenta are just notes to myself.

For control and storage a PC is required. However, in addition to adding the SD card mentioned this could also be made a free-standing device, but that's for later. Though that may require a 40-pin micro to cope with the play/record/track selection/etc. functions. At the moment you could say this is a specialised external sound-card.

The use of a +3.3V supply is becoming increasingly common. There are a few regulators very similar to the usual 78xx series, e.g. the LM1117T-3.3, here I'll simply use an LM317 instead.

Note: R107 has now been removed as it was effectively duplicated.

Steve A.

Move-E-Stor MkII Main !.gif
User avatar
Steve Anderson
"Fester! Don't do that to 'Thing'"
 
Posts: 4854
Joined: Fri Mar 30, 2007 10:54 pm
Location: Bangkok, Thailand

Previous

Return to Electronic NBTV

Who is online

Users browsing this forum: No registered users and 1 guest