Table 3-7. Vocon Clock Distribution; Figure 3-20. Vocon Clock Architecture - Motorola APX 5000 Service Manual

Theory of Operation
: Controller
3.2.3 Clock Sources
The VOCON board contains multiple crystal clock sources. These sources are active upon power-
up. Secondary clock frequencies are derived on the VOCON board from these crystal sources. In
addition to the crystal frequencies, the VOCON receives a 16.8 MHz sine wave from the RF board,
which is shaped into square wave and fed to the OMAP timer input. Screen shots and test points for
these clock signals are shown in
EXPANSION
Clock Frequency
Source
Y6501 24.576 MHz
Y6502 32.768 kHz
Y6601 12 MHz
U6302 96 MHz
U6101 4.096 MHz
U6101 32.768 kHz
Y701 16.8 MHz
(RF
board)
Chapter
RF BOARD
TRIDENT
26 MHz
GPS
MACE

Figure 3-20. VOCON Clock Architecture

Table 3-7. VOCON Clock Distribution

Type
Crystal MAKO 24 MHz & tapped into
Oscillator CPLD
Crystal MAKO RTC
Oscillator
Crystal OMAP CPU Clock
Oscillator
OMAP GPIO DDR Clocks
(Complementary signals)
CPLD GPIO MACE Clock
CPLD GPIO OMAP Boot-Up clock & GPS/
Bluetooth digital clock
Crystal RF Frequency Synthesizer
Oscillator IC (Trident) TCXO
6.
SQUARING
32.768 kHz
CPLD
24.576 MHz
4.096 MHz
Description
U6501, U6101
U6501
U6302
U6301
U2510 (to
Expansion Board)
U6302 & U2401
(Expansion Board)
U6302
VOCON
16.8 MHz
96 MHz
OMAP
12 MHz
32.768 kHz
MAKO
Clock Recipient Suggested Probe
R6574
C6541
C6601
TP6307 & TP6308
R6113
R6114 (GPS/BT) &
R6115 (OMAP)
R6218
3-33
DDR
Points