Table of Contents
Advertisement
Circuit Description
Table 2-1 Hardware Interface Signal Descriptions (Cont.)
SIGNAL
PIN No.
RTS
6 4
CTS
78
RLSD
7 9
XTALI
6 8
XTALO
6 9
PORI
67
V
2 2 , 7 2
D D
V
4 6
c c
G N D D
6 , 7 , 1 6 ,
2 3 , 5 0 , 6 6 ,
7 7 , 8 0 , 8 1 ,
8 9 , 9 2 , 9 7
G N D A
1 7 , 2 1 ,
3 0 , 4 3 , 4 7
5-20
Type
I
Request to send
When the RTS input is forced low, the transmitter starts transmitting the
modem training sequence has been transmitted (signaled by the CTS pin
and CTSB bit becoming active), data present at either the TXDI input pin
in serial mode (PDME bit is reset) or written into the DBFR re g i s t e r i n
parallel mode (PDME bit is set) is modulated and transmitted. The RT S
input pin is logically ORed with the RTSB bit in the interface memory.
O
Clear to send
CTS is used to indicate of that the transmission training sequence has
been completed and the modem is ready to transmit any data pre s e n t a t
either the TXID input pin in serial mode (PDME bit is reset) or in DBFR
in parallel mode (PDME bit is set).
O
Received line signal detector
RLSD becomes active at the end of the reception of the training sequence
indicating the beginning of data reception. If no training is detected but
t h e received energy level is above the RLSD off - t o - o n t h reshold, RLSD
will become active.
I
Oscillator In/Out
O
An external 24.00014MHz (KS16116) or 38.00053 MHz (KS1611 7 ) c r y s t a l
and two capacitors are connected to the XTALI and XTALO.
Alternatively, an external crystal oscillator of the appro p r i a t e f requency
can be connected to the XTALI input leaving XTALO unconnected.
I n o rder to minimize electromagnetic emissions and ensure p roper
oscillator start up and operation, the crystal and the capacitors should be
placed as close as possible to the XTALI and XTALO pins. Further, t h e
c i rcuit board traces connecting the crystal and capacitors to XTALI and
XTALO should be as short as possible. The use of circuit board b i a s
should be avoided in the crystal oscillator circuitry and circuit board
traces should be routed using curved turns.
I
Power On reset In
When power is first applied to the modem, PORI is held low for
approximately 350ms. The modem is turn ready for normal operation
15ms after the low to high transition of PORI.
Power
+5V Digital voltage supply
This pin nust be connected to +5V
supply voltage ripple should not exceed 100mV
Power
+5V Analog voltage supply
This pin nust be connected to +5V
supply voltage ripple should not exceed 100mV
G N D
Digital ground
These pins must be connected to digital ground.
G N D
Analog ground
These pins must be connected to analog ground.
Description
5% supply. The +5V Digital power
p - p .
5% supply. The +5V Analog power
p - p .
Samsung Electronics
Advertisement
Table of Contents
