LICAL-TRC-MT Datasheet, PDF (9/15 Pages) List of Unclassifed Manufacturers – MT SERIES TRANSCODER DATA GUIDE

SERIAL INTERFACE COMMAND SET DEFINITIONS
There are ten functions using the Serial Interface Engine (SIE). Each function
has the ability to read the current setting from the MT or write new information to
the specified configuration setting.
Command
Description
Local Settings
Reads and writes the device’s local 24-bit address and status line
configuration. This allows the option to program all devices with
the same address and status line configuration, or increment the
address to utilize the full range of addresses.
Next User ID
Reads and writes the next available ID location, which will be
given to the next user manually learned into the system.
Specific User
Reads and writes the 24-bit address and status line configuration
for a specific user learned into the system. If a device in the
system is lost or stolen, that specific device can be removed from
the system and replaced with a new one without having to erase
the memory and re-learn all of the other devices in the system.
To remove an existing user, write 0xFF into the address and
status line values. 0xFF should not be used as a learned user.
Target Address
Reads and writes the local device’s 24-bit target address. This
allows a user to communicate directly with a specified target
device and not with any other devices even though they may have
been authorized for communication.
Custom Data Value
Reads and writes a single byte that is sent when Custom Data is
enabled. If enabled, the byte will be sent with each packet, and
then output on the SER_IO line of the receiving device along with
the TX ID value and the status line value.
Latch Mask
Reads and writes the Latch Mask for the status line outputs. This
allows each status line to be individually set as momentary or
latched.
Status Value
Reads the current state of the transcoder’s status line outputs.
Writes the value of the status line inputs to be sent (subject to I/O
mask) and the number of packets to send.
Confirmation EN
Reads and writes the device’s confirmation enable setting. When
enabled, the receiving transcoder will immediately transmit a
confirmation packet back to the originating transcoder. The
originating transcoder will validate the confirmation and then
activate its CONFIRM line. If the confirmation is not necessary or
the user wants to free the air of additional transmissions,
confirmation can be disabled and the receiving device will not
transmit a confirmation packet.
Targeting EN
Reads and writes the device’s target enable setting. This enables
or disables the option for the transcoder to send a targeted data
packet.
Custom Data EN
Reads and writes the transcoder’s custom data setting. This
enables or disables the option for the transcoder to send a custom
data byte with each transmission.
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SERIAL INTERFACE CONNECTIONS
The serial interface on the MT Series can be connected to any device capable
of serial communication, including microcontrollers, RS-232 drivers, and
computers. The figure below gives an example of connecting the MT to the Linx
QS Series USB module for connection to a computer.
USB Type B
Connector
4
GND
3
DAT+
2
DAT -
1
5V
GND
1
2
3
USBDP
USBDM
GND
RI 16
DCD 15
DSR 14
4 VCC
DATA_IN 13
5 SUSP_IND DATA_OUT 12
6 RX_IND
RTS 11
7 TX_IND
8 485_TX
CTS 10
DTR 9
SDM-USB-QS
1
2
3
4 _GND
VCC
V+ ⁸
7
6
NC
5
NC
MAX4544
VCC
1 _VCC
2 _D6
3 _D7
4 _CRT/LRN
5 _{ENC_SEL}
6 _{SER_IO}
7 _CONFIRM
8 _{TR_PDN}
9 _{TR_SEL}
10 _{TR_DATA}
GND ²⁰
D5 ¹⁹
D4 ¹⁸
D3 ¹⁷
LATCH ¹⁶
SEL_BAUD ¹⁵
MODE_IND ¹⁴
D2 ¹³
D1 ¹²
D0 ¹¹
LICAL-TRC-MT
Figure 11: MT Series Transcoder Serial Interface to a PC
The USB module follows the RS-232 convention of using separate lines for data
input and data output while the transcoder has a single line for all data. This
requires a switch to alternatively connect the transcoder’s SER_IO line to the
data lines on the module.
The RTS line is used to throw the switch as well as to activate the CRT/LRN line
placing the transcoder into Serial Mode. This gives the PC the ability to control
when communication is initiated.
The MODE_IND line will go high when the transcoder is prepared to send data,
so the CTS line on the USB module is used to monitor the MODE_IND line. This
allows the computer to know when to throw the switch and look for data from the
transcoder.
One point of note is that voltage translation may be necessary if the 5V USB
module is used to communicate with a transcoder operating at 3V. There are
many components and methods for implementing level shifting, so it is up to the
designer to determine the best solution for the product.
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