Quoted from pinballsp:
Two days ago I received already the PCB for the DMDMK66 192*64, I will assemble and test along this week.
I have check the SD card access by SDIO 4 bit parallel, and its really VERY FAST, these are my Test Results, read/write between 16 and 19Mb/s. So, with so fast access, its enough to store files with full colored games, do not need external flash memory chip.
Also Im testing a new DC-DC switched circuit for this DMD 192*64, because the quantity of leds are 3 times more than the 128*32, so need a stronger circuit to connect directly to 12/18 VDC (do not need external AC Power Supply).
So, my DMDMK66 192*64 will be 100% Plug and Play, very compact and lightweight. Remove old DMD, connect DMDMK66 192*64 and work immediately, do not need external AC high voltage power supply, do not need connect any special cable, do not need key licenses, do not need wait for any activation, connect and work.
Im really very happy will all tests Im doing with DMDMK66 192*64, I think will be a very good product, high quality, very good features. And also Im working with the Software to color games for ALL my DMD, I have contact with a mexican software programmer to help me with it, because of Im very busy with hardware and firmware development.
If you plan to use it as a card reader without display output or any other process running this may be true, but
instead of measuring some theoretical values you could have had a look at the demands of your application and see that SD card communication has never been a bottleneck.
You need as maximum :
192x64 pixel = 1536 byte per frame multiplied with 24bit color depth and 60 frames per second = 2160kB/sec
So even if you communicate with the SD in 1bit mode it is more than fast enough.
But there are other hurdles to take ...