MSP430FR5994: Set the delay for 0.1us

Hi,

Please try with this demo code to set the MCLK to 8MHz.

https://dev.ti.com/tirex/explore/node?node=A__AET-GYwzL1YU7YHGoqxhGQ__msp430ware__IOGqZri__LATEST

Best regards,

Cash Hao

Thank you.

Do you mean that I can use a 10 MHz external crystal or oscillator connected to the HFXT (High-Frequency Crystal) pins and set the system clock to use this external clock source?

Yes, that would be the idea. The FR59 series clock system only provides a specific set of DCO frequencies, and  I don't see 10MHz among them.

Looking more closely at User Guide (SLAU367P) Tables 3-5/3-7: Using DCORSEL=1, DCOFSEL=5, and DIVS=1 you could get 21/2=10.5MHz from SMCLK. Would that be close enough?

I have tried to set the SMCLK to 10.5MHz. However, I found my UART port unable to receive the correct data.

This is the parameter I used to setup the uart.

I don't know offhand. It seems a little odd that it's recommending oversampling (UCOS16=1), since my desk calculator says that BRW=91 (UCOS16=0) with no modulation gets within 0.2%.

I just tried the UART both ways and had no obvious difficulty with Rx or Tx.

What is incorrect about the Rx data you see?

I don't see anything obviously wrong here. How certain are you that your clock is correct?

What is incorrect about the Rx data you see? (Bit errors? Overruns? Nothing at all?)

For reference, here's what I wrote for the UART:

#if NO_MOD
    UCA0BRW = HZ / UART_BPS;        // Oughta round, but not needed now
#else
    UCA0BRW = 5;
    UCA0MCTLW = (32u << 8) | (11u << 4) | UCOS16; // BRF=11, BRS=32, 16x
#endif

and for the clock:

#elif (HZ == 10500000UL)
	FRCTL0 = FRCTLPW | NWAITS_1;
	CSCTL0 = 0xA500;
	CSCTL3 = DIVA_0 | DIVS_1 | DIVM_1; // SMCLK=MCLK=DCO/2
	CSCTL1 = DCOFSEL_5 | DCORSEL;   // RSEL=1, FSEL=5 -> 21MHz per Table 3-5
#endif

[Edit: Minor clarification]

This is my clock setup.

What is incorrect about the Rx data you see? (Bit errors? Overruns? Nothing at all?)
 >>I have configured some response commands for the MCU, but while some commands work, others do not. I suspect there might be errors occurring during the RX process.