Hi, there is also a similar problem on my device. We have added 512 KB external SRAM to our K60n512 board. The initialization function is the same as described above (as the code from Todd) or in AN4393, except the following
// Set FlexBus Base address for CS0.
FB->CS.CSAR = 0x70000000;
// Set CS control register for CS0. Addr s&h, 4 WS, AutoAck, 8bit port.
FB->CS.CSCR = FB_CSCR_ASET(1) | FB_CSCR_RDAH(1) | FB_CSCR_WS(4) |
FB_CSCR_AA_MASK | FB_CSCR_PS(1);
// Set FlexBus Base address mask for CS0 and set valid (enable).
FB->CS.CSMR = FB_CSMR_BAM(0x07) | FB_CSMR_V_MASK;
When checking FB_CS0 in the oscilloscope while doing some read/write at base address, no signals can be observed from FB_CS0.
It would be appreciated if anyone could provide some possible hints or information about this problem.