ZHCS894U April 2001 – July 2019 TMS320F2810 , TMS320F2811 , TMS320F2812
PRODUCTION DATA.
请参考 PDF 数据表获取器件具体的封装图。
The F281x has an on-chip, PLL-based clock module. This module provides all the necessary clocking signals for the device, as well as control for low-power mode entry. The PLL has a 4-bit ratio control to select different CPU clock rates. The watchdog module should be disabled before writing to the PLLCR register. It can be re-enabled (if need be) after the PLL module has stabilized, which takes 131072 XCLKIN cycles.
The PLL-based clock module provides two modes of operation:
PLL MODE | REMARKS | SYSCLKOUT |
---|---|---|
PLL Disabled | Invoked by tying XPLLDIS pin low upon reset. PLL block is completely disabled. Clock input to the CPU (CLKIN) is directly derived from the clock signal present at the X1/XCLKIN pin. | XCLKIN |
PLL Bypassed | Default PLL configuration upon power-up, if PLL is not disabled. The PLL itself is bypassed. However, the /2 module in the PLL block divides the clock input at the X1/XCLKIN pin by two before feeding it to the CPU. | XCLKIN/2 |
PLL Enabled | Achieved by writing a non-zero value “n” into PLLCR register. The /2 module in the PLL block now divides the output of the PLL by two before feeding it to the CPU. | (XCLKIN * n) / 2 |