Hi, I'm undergrad working on project that invovles data transfering from a Xilinix Chip on a PCB to computer using removable media.


I had been studying the smartMedia format for some time now. Here is my idea of a firmware that will work on one type of SmartMedia card(8mb)

goal:
write enable + 8 bit data line -> smart media card (22 lines)

1. write the serial input command to the command latch
2. sets up the col and page address to the address register(setting it to point to the very first byte of the first block of the first page)
3. leave the program in a waiting state
4. once the write enable signal is triggered, output the actual data(ascii decimal) to the card
5. once the write enable signal is dropped, terminate the writing action
6. remove the smart media
7. now that the raw data is in the chip, use the unix utility dd (disk dump) to convert the raw data to an ascii file...

I know that the SSFDC forum has the full functional firmware for free, but I don't want to use it since we do not want all the junk features, like the ECC and power code.
I don't even have a proper smartmedia card connector. It is just 22 wires connect directly to the card...

I will be using Xilinx foundation to implment my design. The PCB is already set up. Hardware shouldn't be an issue. The clk is definitely fast enough for smartmedia

Well, I had consider putting FAT12 format on the card then write to it but that turns out to be very complicated. There are some people who recommended me to use MMC instead of SmartMedia since it only has 4 lines. But I don't have any MMC spec and according to their website only payed developer can access them.

smartmedia spec is free but you have to register with the SSFDC. If anyone wants them, I'm going to save you the trouble
http://www.sfu.ca/~pyuan/sm/

what I want to know is:
has someone done something similar before. If so, does what I'm about to do sound feasible? Am I overlooking any issue?


Thanks for any input!

 

bump

come on, you microcontroller lovers :P

 

There's documentation out there for SD cards (superset of MMC) and it only requires a simple 4 wire SPI interface.

__________________
Mark Higgins

 

I think I posted this before, but here is a link with at least some of what you need to get started http://ourworld.compuserve.com/homep...r/ssfdclog.htm

 

I think I posted this before, but here is a link with at least some of what you need to get started http://ourworld.compuserve.com/homep...r/ssfdclog.htm

 

Hi,

You are the Nth person trying to convert me to MMC

Yes I know it's simpler but currently two obstacles are preventing me from switching

1. I had already spent a considerable amount of time studying smartMedia, and had already setup the hardware

2. More importantly, although a lot of people talk about MMC, I still do not have my hands on its design spec. Without the spec I cannot do anything. I google a bit and found out that the official MMC/SD forum wants affiliates(basically companies) to pay $ for the sepc. So even though it might be a lot easier to write MMC data logger in VHDL, it's off the table for the momment.

If I have the spec then we will be talking :wink:

And oh, although I want to write custom VHDL since it will be a very good learning experience, it's not against the law to use off-the-shelf VHDL code

 

Hi,

Well, this guy had discontinued his project since SM isn't taking off. Our goal is the same, but we use totally different method (let's just hope that we don't ended up with the same result...)

He uses a PIC since that's what people normally use. I use FPGA(VHDL) since half of the project is already. The data logger SM writer is really just a bonus for the project.

 

Anyways, I guess my idea isn't very popular. I just want seasoned developer to take a look at my idea and give me a heads up if there is something wrong with it

By the way, I had read over all the smartMedia spec doc in the following URL

http://www.sfu.ca/~pyuan/sm/

 

last bump :cry:

Anyways, I think going to give my idea a shot...