Figure 3-12. Control Top Flex - Motorola ASTRO XTS 5000 Detailed Service Manual

Theory of Operation
: VOCON Board
LED D1 is the TX/RX indicator. LEDs D2 through D6 are used for backlighting the frequency knob.
U1 is a binary-coded switch. The output pins from U1, which are connected to GPIO pins on the
Patriot IC, provide a four-bit binary word (signals RTA0, RTA1, RTA2, and RTA3) to the MCU,
indicating to which of the 16 positions the rotary is set. This switch provides an additional output,
TG2, which is typically used for coded or clear mode selection. It is an input to the Patriot IC
TOUT8_PD4 GPIO pin. Selecting clear mode pulls this signal to a logic low, and it can be monitored
from R234.
To Controller
J101
UNSW_B+ (33)
V2 (35)
TOGGLE SWITCH (TG1)
VOL (31)
EMERG (14)
B+_SENSE (32)
GREEN_LED (22)
RED_LED (21)
INT_PTT* (38)
RTA0 (27)
RTA1 (24)
RTA2 (26)
RTA3 (25)
SECURE/CLEAR (TG2)
SWITCH (23)
DGND (15)
MONITOR (17)
BL_EN (20)
INT_SPKR (40)
SPKR_COM (37)
INT_MIC (36)
AGND (39)
3.2.4.8 System Clocks
The Patriot IC is supplied with two clocks. The first clock, a 16.8 MHz sine wave, comes from the RF
interface connector P201 pin 7. It is conditioned by the clock buffer circuit, which includes Q450,
Q451, L450, C450, C452, C452, R450, R451, R452, R453, R454, and R455. The output of this
buffer (C452) goes to the Patriot IC CKIH pin as well as the Flipper IC REF_16_IN (C307).
6881094C31-E
S1
S901
R901
ON/OFF
3
5 4
(34)
1
U1
2
Zone/Channel
4
Select
8
B
C C A
1
2
1
C1
2

Figure 3-12. Control Top Flex

VOL
V2
1
2
R1
91K
V2
D1
4
3
R2
68K
2 1
R3
150K
SW2
PTT
V2
LS1
MIC
SW3
TOP BUTTON
2 1
S2
TOGGLE
SWITCH
SB1
(MON)
SB2
SB3
D2 D3
4 4 3
3
1
2 1 2
D5 D6
4 3 4 3
1 1
2 2
D4
4 3
1
2
MAEPF-27416-A
November 16, 2006
3-37
V2