i want to make oscilloscope
stm32 with cpld epm240 and ad9288@100mhz
i will use 320*240 lcd
the question is
i want to save and record adc buffer only
320byte(for lcd)
the epm240 have internal memory 8192 bit
can i use it in my project or it's rom not ram
If you plan on using it as a buffer for the ADC expect the flash to wear out and the epm240 needing to be replaced periodically (depending on usage). You'll also suffer from long erase times to clear out each of the 4096-bit sectors so don't expect to have any real time update of you oscilloscope.
You might want to consider something more like a Zynq which has a built in ARM along with FPGA resources (including lots of RAM) to support the AD9288 interfacing.
If you really want to stick to a CPLD then get an actual external SRAM device to store the ADC data.
thank you
then i will use fpga
because the cost of $sram+$cpld=$fpga
with fpga i not need external sram ?????
i need 240 byte only at 100mhz write speed
Use a Cyclone or a Spartan/Artix part, they can also support implementing an embedded processor if you are inclined to reduce the parts count further. Even the smallest of the parts will have 100's or more Kbits of SRAM (internal block RAMs) that can be used.
From Altera portfolio, a small MAX10 "CPLD" (actually a small Cyclone III/IV FPGA core with flash configuration memory and single supply option) can be used as DSO controller and storage solution.
Nice they also seem to have block RAM. They could also go with say a Lattice Semiconductor part or an Actel/Microsemi part both of those are generally very very inexpensive compared to what you typically see from both Altera and Xilinx, though the tools tend to be rubbish in comparison to the big two.