Hexin Technology HXJZ-881 1000m-1500m Micro Power RS-232/RS-485/TTL to RF Wireless Module - Manual (Page 4)

2.HXJZ-881 interface definition
1) User’s interface
HXJZ-881 have one interface of TTL.
In standard interface, the plastic socket gap upward, from left to right,1-8 pin in turn, as follows;
Definition of connecting pins and connection method:
Item no PIN Description User’s terminal Remarks
1 VCC +5±0.5V +5V 3V is possible for user
2 GND Power supply/Ground DGND/AGND
3 TXD Serial data transmitting TTL User receiving
4 RXD Serial data receiving TTL User transmitting
5 RXD/RS-485(A) Serial data receiving TXD/RS-485(A) User transmitting
6 TXD/RS-485(B) Serial data transmitting RXD/RS-485(B) User receiving
7 SLE Sleeping control Don't’ open
8 GND Power supply/Ground DGND/AGND
Remarks:
a. HXJZ-881 with sleeping function is not open in default ,if the user need ,then you must say it clearly
when you place an order.
b. The standard power supply is 5V ,if the user need 3V ,then must tell us before place an order.
2) Power supply
HXJZ-881 uses DC power supply with voltage of +5V. It can also share power supply with other
equipment, however, the high quality power supply with desirable ripple factor should be selected. In addition,
the reliable grounding must be used if there is other device in the system equipment. In case of failure to
connect with the earth, it can form its own grounding, but it must be absolutely separated from the municipal
electric supply.
3). Power Saving model
HXJZ-881 consists of Sleeping Model and Non-sleeping model. The power is 10Ua when sleeping. The
user need to specify which model you need .
Awaken from Hardware, you can input high level in 7pin, then it sleep.
If don’t need sleep ,then u can connect 7 pin to ground. It will not sleep.
3. HXJZ-881 Parameters Setting
HXJZ-881 have one interface of TTL.
HXJZ-881 main parameters: COM baud rate and verify, RF baud rate, Channel and frequency.
You can change these parameters by our RF Module soft. When RF baud rate is faster than COM baud rate，
One frame Can transmit limitless data. When RF baud rate is not faster than COM baud rate, one frame can
transmit 255 bytes most. You can set the rate according your need.
Two HXJZ-881 communicate must have condition as follow:
1.Their channels (i.e. frequency) are the same.
2.Their RF rates are the same.
3.RF Module Com baud rate and verify is agree with its equipment or PC that it connects with.