Motorola Professional GP680 Informasi Layanan - Halaman 7

Jelajahi secara online atau unduh pdf Informasi Layanan untuk Radio Motorola Professional GP680. Motorola Professional GP680 30 halaman. Professional radio, power distribution and controller
Juga untuk Motorola Professional GP680: Panduan Pengguna (18 halaman), Informasi Layanan (28 halaman), Informasi Layanan (32 halaman), Informasi Layanan (30 halaman), Informasi Layanan (26 halaman), Informasi Layanan (43 halaman)

Halaman Cetak
Motorola Professional GP680 Informasi Layanan
Controller Circuits
Conventional MDC
Conventional 5 Tone
Conventional 5 Tone
Privacy Plus
SmartZone
MPT
MPT
3.3

Real Time Clock

( Refer to Figure 1-3 and the Microprocessor schematic diagram )
Radios with displays support a Real Time Clock (RTC) module for purposes of message time
stamping and time keeping. The RTC module resides in the microcontroller.The clock uses a back-
up Lithium Ion battery for operating power when the primary battery is removed.
3.3.1
Circuit Description
The RTC module circuit, shown in Figure 1-3, is powered by the ModB/Vstby pin and PI6/PI7 from
the crystal oscillator circuit. A clock frequency of 38.4kHz from a crystal oscillator provides the
reference signal which is divided down to 1 Hz in the processor.
HC11FL0
MODA
MODB
PI6
PI7
As the RTC module is powered separately from the processor Vdd, the RTC is kept active through
the ModB / Vstby pin which provides the Lithium battery back-up power when the radio is switched
off.
Table 1-1 Radio Memory Requirements
RADIO
GP140
GP320, GP340
GP360, GP380
GP240, GP280
GP540, GP580
GP640, GP680
GP1280
FL401
C436
OUT
R420
38.4kHz
GND
IN
R426
C437
Figure 1-3 RTC Circuit
ROM (KB)
128K
512K
512K
512K
512K
512K
512K
Vddd
R461
C435
CR411
1
Q416
2
3
2
1
R462
R463
CR413
300
5
1
4
Q417
3
2
1
6
2
UNSWB+
SWB+
3
4
EXT RAM
EEPROM
(KB)
(KB)
-
8K
16K
16K
16K
16K
16K
16K
16K
16K
16K
16K
16K
16K
UNSWB+
U410
3.3V
2
3
VIN VOUT
C434
R460
5
4
R419
3
LI_ION
BOOT_CTRL
TP405
TEST_POINT
1-3