1 introduction to the clock generation module, Introduction to the clock generation module -2, Table 4-1 – Motorola MC68VZ328 User Manual
Page 70: Cgm clock signal distribution -2
4-2
MC68VZ328 User’s Manual
Introduction to the Clock Generation Module
4.1
Introduction to the Clock Generation Module
The CGM produces four clock signals:
•
CLK32—A low-frequency reference clock used by almost every module
•
DMACLK—Used to create the remaining two clocks, and serves as DMA clock for the LCD
controller
•
SYSCLK—Used by most modules, including the CPU
•
LCDCLK—Used as reference by the LCD
The distribution of the clock signals generated by the CGM is shown in Table 4-1. With the exception of
the CLK32 signal, the frequency of the clock signals can be individually programmed.
Table 4-1. CGM Clock Signal Distribution
Used by or Available To
CLK32
SYSCLK
DMACLK
LCDCLK
CLKO/PF2 pin
X
DRAM controller
X
X
X
LCD controller
X
X
PCM
X
PWM
X
X
RTC
X
SPIs
X
Timers
X
X
UARTs
X