SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
When using synchronous interface protocols, the GPMC_CLK output only toggles during the read or write access cycle. In some applications, it may be desirable to have a continuous clock running at the GPMC interface clock frequency for clocking attached devices. This option is enabled by an optional clock path from the GPMC functional clock input to the GPMC_CLKOUT pin. This clock output (GPMC_FCLK_MUX) can be selected through the standard MUXMODE selection of the GPMC_CLKOUT pin PADCONFIG control register. (See device Pin Muxing for details.).
Note that when using synchronous interface protocols with the continuous clock option described above, the programmer should ensure that the GPMC outputs are timed to the same frequency. (GPMC_CONFIG1_x GPMCFCLKDIVIDER = 0). The GPMC_CLK is also output to two pads for signal integrity reasons. One pad is intended for board level use and one is for IO loopback.