I am using LPC4088 based custom board with Nor Flash(SST39VF3202C), SRAM(CY62157EV30LL) & FGPA all working on the EMC. The CPU, Peripheral & EMC all are working on 72 MHz.
A secondary USB custom bootloader is in internal Flash. The user code is stored in external Nor flash. Wait states are same as in "norflash_prog" in LPCOpen example code & also I enable buffer mode just before jumping to user application(which helped to improve execution speed).
I am able to store generated S19 file into external flash using USB bootloader & it runs as well but it executes very slowly. The whole program seems to be lagging even without delay.
Due to this I cannot generate timer interrupt of <(100 us)(which is near about 2.5 us in internal flash) & that too not precise.
The nor flash does not support page read mode so I will try S29GL064S which has page read mode & is also pin compatible.
In many discussions I read that SPIFI based flash is faster than parallel nor flash. how?
What else can I do? Any suggestions would be helpful.