TAN-16 Datasheet, PDF (1/6 Pages) Exar Corporation – How to Generate a 1.544MHz (or 2.048MHz) Clock Signal from an 8kHz Reference Clock

TAN-16
How to Generate a 1.544MHz (or 2.048MHz)
Clock Signal from an 8kHz Reference Clock
The XRT8000 device can be configured to generate either a T1 (1.544MHz) or E1
(2.048MHz) rate clock signal, from a “Reference Clock signal of frequency 8kHz. The
approach that one should use to accomplish all of this is presented below.
1. To generate a 1.544MHz clock signal, from an 8kHz clock signal:
July 1998-2
8 kHz
XR-T8000
FIN
CLK1
CLK2
1.544 MHz
1.544 MHz
MSB
(CONFIG.)
Microcontroller Serial Interface
Figure 1. Illustration of the XRT8000 device generating a 1.544MHz
clock signal from an 8kHz Reference clock signal (Reverse/Slave Mode).
In order to configure the XRT8000 device to operate in this manner, the user must config-
ure the chip to operate in the “Reverse/Slave” Mode. The user accomplishes this by
executing the following steps:
* Pull the MSB pin (pin 8) “low”.
This will configure the device to operate in the “Slave” Mode.
* Write the following values, into the corresponding “Configuration Registers”,
(via the Microprocessor Serial Interface) as tabulated below in Table 1.
Rev. 1.00
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