SPRUIV7B May 2022 – September 2023 AM620-Q1 , AM623 , AM625 , AM625-Q1 , AM625SIP
MCU_OBSCLK0 output is controlled by MCU_CTRL_MMR_CFG0_MCU_OBSCLK_CTRL register in the MCU_CTRL_MMR0 module; for more information about control registers, refer to Control Module (CTRL_MMR). Two muxes are connected in series - MCU_OBSCLK0_MUX0 and MCU_OBSCLK0_MUX1, see Figure 6-33.
How to select the output of MCU_OBSCLK0_MUX1 is described in Table 6-24.
MCU_CTRL_MMR_CFG0_MCU_OBSCLK_CTRL(2)[3-0] CLK_SEL |
MCU_OBSCLK0_MUX1 Output Clock Selection(1) |
---|---|
0x0 | CLK_12M_RC |
0x1 | 0 (GND)(3) |
0x2 | MCU_PLL0_HSDIV0_CLKOUT |
0x3 | MCU_PLL0_HSDIV4_CLKOUT |
0x4 | MCU_PLLCTRL0_PLL_CTRL_OBSCLK_CLK |
0x5 | CLK_32K_RC |
0x6 | HFOSC0_CLKOUT |
0x7 | HFOSC0_CLKOUT_32K |
0x8 | MCU_SYSCLK0 |
0x9 | DEVICE_CLKOUT_32K |
0xA-0xF | RESERVED(3) |
The value of the software-controlled 4-bit divider is determined by the MCU_CTRL_MMR_CFG0_MCU_OBSCLK_CTRL[11-8] CLK _DIV field; for more information about control registers, see Control Module (CTRL_MMR).
MCU_OBSCLK1_MUX0 is provided as a low jitter output for HFOSC0_CLK. In this configuration, MCU_CTRL_MMR_CFG0_MCU_OBSCLK_CTRL[3-0] should be configured as 0x1 (1, selecting a logical low signal) and MCU_CTRL_MMR_CFG0_MCU_OBSCLK_CTRL[24] should be configured as 0x1.