ZHCSI67D May 2018 – December 2019 MSP430FR2153 , MSP430FR2155 , MSP430FR2353 , MSP430FR2355
PRODUCTION DATA.
The clock system includes a 32-kHz low-frequency or up to 24-MHz high-frequency crystal oscillator (XT1), an internal very low-power low-frequency oscillator (VLO), an integrated 32-kHz RC oscillator (REFO), an integrated internal digitally controlled oscillator (DCO) that can use frequency-locked loop (FLL) locking with internal or external 32-kHz reference clock, and on-chip asynchronous high-speed clock (MODOSC). The clock system is designed to target cost-effective designs with minimal external components. A fail-safe mechanism is designed for XT1. The clock system module supports the following clock signals.
All peripherals have one or several clock sources, depending on specific functionality. Table 5-9 lists the clock distribution used in this device.
| CLOCK SOURCE SELECT BITS | MCLK | SMCLK | ACLK | MODCLK | VLOCLK | EXTERNAL PIN | |
|---|---|---|---|---|---|---|---|
| Frequency Range | DC to 24 MHz | DC to 24 MHz | DC to 40 kHz | 3.8 MHz ±21% | 10 kHz ±50% | – | |
| CPU | N/A | Default | – | – | – | – | – |
| FRAM | N/A | Default | – | – | – | – | – |
| RAM | N/A | Default | – | – | – | – | – |
| CRC | N/A | Default | – | – | – | – | – |
| MPY32 | N/A | Default | – | – | – | – | – |
| ICC | N/A | Default | – | – | – | – | – |
| I/O | N/A | Default | – | – | – | – | – |
| TB0 | TBSSEL | – | 10b | 01b | – | – | 00b (TB0CLK pin) |
| TB1 | TBSSEL | – | 10b | 01b | – | – | 00b (TB1CLK pin) |
| TB2 | TBSSEL | – | 10b | 01b | – | – | 00b (TB2CLK pin) |
| TB3 | TBSSEL | – | 10b | 01b | – | – | 00b (TB3CLK pin) |
| eUSCI_A0 | UCSSEL | – | 10b or 11b | 01b | – | – | 00b (UCA0CLK pin) |
| eUSCI_A1 | UCSSEL | – | 10b or 11b | 01b | – | – | 00b (UCA1CLK pin) |
| eUSCI_B0 | UCSSEL | – | 10b or 11b | 01b | – | – | 00b (UCB0CLK pin) |
| eUSCI_B1 | UCSSEL | – | 10b or 11b | 01b | – | – | 00b (UCB1CLK pin) |
| MFM | N/A | – | Default | – | – | – | – |
| WDT | WDTSSEL | – | 00b | 01b | – | 10b | – |
| ADC | ADCSSEL | – | 10b or 11b | 01b | 00b | – | – |
| RTC Counter | RTCSS | – | 01b(1) | 01b(1) | – | 11b | – |
| OPERATION MODE | CLOCK SOURCE SELECT BITS | XTHFCLK | XTLFCLK | XTLFCLK (LPMx.5) |
|---|---|---|---|---|
| AM to LPM0 | AM to LPM3 | AM to LPM3.5 | ||
| MCLK | SELMS | 10b | 10b | 10b |
| SMCLK | SELMS | 10b | 10b | 10b |
| REFO | SELREF | 0b | 0b | 0b |
| ACLK | SELA | 0b | 0b | 0b |
| RTC | RTCSS | – | 10b | 10b |