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a)
Clock Generation :
Crystal Input Clock (TCLK and XTAL). This is the input pair to an internal crystal oscillator and
corresponding logic. A 14.318 MHz crystal is recommended.
b)
Hardware Reset ( Pin 17):
Hardware Reset signal is generated by MAX6326 (U5).It asserts a reset signal for at least 100 ms.
c)
Analog to Digital Converter:
The gm2121 chip has three ADC's (analog-to-digital converters), one for each color (red, green and
blue) .The analog RGB signals are connected to gm2121 as described
below
d)
OSD: The gm2121 has a fully programmable, high-quality OSD controller. The on-chip static RAM (4096
words by 24 bits) stores the cell map and the cell definitions.
e)
On-Chip Micro controller (OCM): The gm2121 on-chip micro controller (OCM) serves as the system micro
controller. That is, it programs the gm2121 and manages other devices in the system such as the keypad, the
backlight, LED, audio and non-volatile RAM. Using general purpose input/output (GPIO) pins.
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