I’m an FPGA programmer and I’ve begun developing an FPGA board to interface with the PSP LCD.
My goals are to provide both a usb interface for tethering to a computer, as well as an SPI/I2C interface for a microcontroller.
On a separate board I have the FPGA/usb interface working, so I will mostly be adding in the backlight/lcd connectors and swapping out DDR ram for SDRAM.
Currently the design features:
Spartan 3E-100/250 TQFP and xilinx prom.
CY7C68013A (High speed usb 2.0) connecting to FPGA
Backlight inverter with appropriate LCD connections
Designated I2C/SPI connections to Spartan 3E
SDRAM (currently @ 100 Mhz/16-bit in simulation)
Any other features you would like? The USB2.0 interface and mild compression should allow for video easily at the low dot clock (9.0Mhz).
How much realistic interest is there in the project?
Would it be preferable to have a cheaper CPLD with connection to the psp lcd and small ram without usb etc? SPI should still be readily doable with a large CPLD.
Any thoughts are appreciated before I finish up the board!
I have noticed that prices for SDR SDRAM have been rising (and DDR to some extent) while DDR and DDR2 are staying the same or falling due to commoditization (is that even a word??) in PC’s while SDR SDRAM has fallen out of favor there…
I would think that DDR would be a cheaper choice, or am I wrong in that assumption?
Cost: as David said, they are relatively comparable, but still cheaper by a good bit for SDRAM.
Data rate: The PSP LCD is 9MhzX24bit, so with horizontal/vertical sync timing and the FPGAs block rams, it is quite easy to run a slower ram clock.
Ideally I would use lower power mobile DDR-SDRAM but those are only available in BGA, although they are affordable. That’s an option for a respin if I can reliably test them post-hotair soldering.
I think the board would have to offer an easy mechanism for basic block operations, text, and some animation to have any appeal to the hobbiest market. I doubt most people want the hassle of installing the FPGA toolchain.
I would also be seriously interested in this board as I have gained two PSP screens in the last few months. How much do you think would this be costing? I personally would not need it to be able to show video but if it is not extremely expensive then it would be quite cool to have…
This week we receive the first pcb samples to be used ad breakout or demo board for a 4.3TFT panel. We are going to test the display, a small cpld and a new controller.
May be if we get more than 3-4 pcb we can share one of them .
I think you just need the pcb with fpc connectors and the backlt step-up. Since we have provided a standard 0.1" connector with lcd signals you can use this board as connector converter (from std flat to fpc flat).
we get 3-4 pcbs … one is currently well running … one more i sent to a friend i can share to you just the last sample … but i found on it some short circuit and i need to repair it
because of emi noise we decided to make a new version without expansion connector
so now we have several board with PSP connector + backlight step-up converter + 1 cpld + 1 ram + 1 small cpu usign the AD channels to sample the touch screen
the external interfaces are:
RS232 or RS485 serial port
optional on request a CAN serial port
2 digital/analog inputs useful to connect switches or buttons
optional sd card
it’s not a true breakout board but the cost is about 50€ and is similar to the breakout/demo board … (we have only few euros added by the cpu)
you just need to send commands from your (i think robot ?) using a RS232 or CAN instead of a parallel port …
please note we can supply 16color or 256 color … actually we do not support 16k colors
I’m afraid I’m a bit caught up in a load of other projects at the moment so will have to pass on that offer. I will keep it in mind that something has been made for it now for when I get round to thinking of using one of the LCDs.