Today, we have an architecture for our project, I hope that’s the last one.
I tried to chose all of the components to be able to start the schematic of the PCB.
- We had already chosen the Gumstix module (Overo® AirSTORM COM), here it is : https://www.gumstix.com/store/product_info.php?products_id=266
- For the RAM, with the last architecture, we had to keep only 2 cylinders. That’s why we have chosen to use a 512K*16bits SRAM (32*32*256) : http://fr.farnell.com/alliance-memory/as7c38098a-10tin/sram-8mb-512kx16-3-3v-44tsopii/dp/2103743
- For the led Driver we needed a 24bin module for control 8 leds RGB with an access rate higher than 12.5Mbit/s ( 256pos*16cylinder*16lines*24pinPerDriver*8bitsDataPerPin), here is a driver with 30Mbit/s : http://fr.farnell.com/texas-instruments/tlc5947dap/ic-led-driver-linear-32-tssop/dp/1755259
- For the incremental encoder, we need 16 rotations per second = 960 rotation per minute. we needed at least 256 positions : http://fr.farnell.com/kubler/05-2400-1122-1024/codeur-incremental-1024ppr-2400/dp/4729535
For the FPGA we had to know how much pin we needed the result is :
- 8*Drivers : 2 pins de configuration.
- 2*RAM : 16 pins data // 19 pins address // 6 pins configuration.
- 1*Gumstix : 27 pins communication.
- 1*Incremental encoder : 2 pins for the incremental count.
- 1*multiplexer : 4 pins for 16 positions (we have 32 lines of led but at the same time with the 8 drivers we have two line connected.
The result is at least 131 pins for the FPGA : http://fr.farnell.com/altera/ep3c16q240c8n/fpga-cyclone-iii-16k-le-pqfp240/dp/1549365
We need some verifications and when we have them we can start to do the schematic for the PCB.