On our board design, we have two QSPI Flash Chips (1Gb each) that we will be operating in parallel mode on a LS1046A. We are using the Flash Programmer utility in Code Warrior (version 11.5.12) to program the devices. When we program QSPI A flash (Starting Address 0x40000000), everything works as expected. When we attempt to program QSPI B flash (0x48000000), the data is not written to flash. We also cannot successfully execute erase commands. If we program the QSPI B chip using an external device (Corelis JTAG), we are able to successfully read in parallel mode.
Upon investigation of the problem, we instrumented the QSPI Clock, Chip Select, and 4 data lines for the two QSPI chips. When we issue an Erase command on QSPI A, we see a series of commands go out the QSPI A bus. I think it’s a status register read, another status register read, a write enable, a status register read, and finally a series of sector erase commands. This works as expected.
When we issue the Erase command on QSPI B, the same set of commands are sent but the status register read and write enable commands are transmitted out to the QSPI A device while the Erase is sent to the QSPI B device. Since the QSPI B device has not received the WRITE enable command, the Erase does not work. I’ve attached a scope capture that shows this behavior.
Here are the scope signals:
D0 – QSPI_A Clock
D1 – QSPI_A Chip Select
D2 – QSPI_A D0
D3 – QSPI_A D1
D4 – QSPI_A D2
D5 – QSPI_A D3
D6 – QSPI_B Clock
D7 – QSPI_B Chip Select
D8 – QSPI_B D0
D9 – QSPI_B D1
D10 – QSPI_B D2
D11 – QSPI_B D3
Any ideas on what may be going on to cause this behavior?
