ZULU Modem
Pin Descriptions:
RX, TX
This is the Data Input / Output. Data is transmitted and received at the low voltage level
(dependant on Vcc being used). Compatible with LCTTL / LVCMOS
Serial Data Format
Baud Rate:
Data Bits:
Parity:
Defined by DR1 and DR2 Pins
8
None
Stop Bits:
Flow Control:
1
Hardware CTS / RTS
CTS, RTS
Clear to Send and Request to Send are standard data flow control used in RS232 systems,
these are standard but operate at the Zulu Vcc low level voltage.
If no handshaking required RTS may be pulled low, however beware of data overrun errors of
transmitting streams of data longer than the data buffer!
RESET
Connection to GND Resets the Zulu Module. Zulu Modem starts up when this input is taken
from GND to Vcc. Normal operation: connect to Vcc through a 10Kohm Resistor
DR1
DR2
Host Baud Rate
Vcc / Unconnected
Vcc / Unconnected
GND
Vcc / Unconnected
GND
Vcc / Unconnected
GND
4,800
9,600
19,200
38,400
GND
Vcc:
Supply Voltage (2.2—3.6V)
DR1 - DR2
These inputs define the host interface Baud Rate. They are read when RESET pin goes high.
Tip: It is good practice to operate the host interface at half the speed of the RF data rate (set
by Register R5
PD
This input enables ‘Sleep’ Mode. For normal operation connect to Vcc. No RF packets will be
received by the module when it is in sleep mode.
WRE
Controls where the User configuration parameters are saved in internal EEPROM (Non-
Volatile) or RAM (Volatile) Un-used. Thiis may be ignored unless the application requires specif-
ic address timimng on powerup.
Tx / Rx LED
Direct LED Drive which operates whenever there is RF activity.
XTAL1, XTAL2
The Zulu module requires a 30MHz drive Crystal to be connected between XTAL1-2
Any standard crystal +/-10ppm ~20pF such as FEC 184-2247.
DS-ZULUM-2
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