Supports RS-232C, TTL(UART)

Line Monitor



Handheld analyzer for TTL(1.8V-5V)
with touch screen.

4.3 inch color touch screen
Preset speeds up to 460.8Kbps
Real-time display of communication data
Supports USB flash as strage device
Handheld, 5 hours work by AA size Ni-MH battery

LE-120SA is a handheld line monitor specialized for ASYNC communication which is widely used in the industry. You can control the line monitor by soft screen touch as you do for smart phones. The light weight (300g including batteries) helps you for the field maintenance besides the system developments.

<Carrying bag image>

Supports RS-232C and 1.8V/2.5V/3.3V/5V TTL(UART)

LE-120SA supports RS-232C and 1.8V/2.5V/3.3V/5V TTL(UART) which is popular for communication between ICs on printed circuit boards.

RS-232C port, TTL and external trigger port.

TTL and external trigger port

<Measurement port and Function setting>

Simple and Easy Setting

You only need to select one of the pre-set speeds and data framing for configuration as we have omitted support for unique specifications. Also the online monitor has the Monitor Condition Auto Setting function for the monitoring of a communication of unknown specification.

<Configuration display>

Common speeds up to 460.8Kbps are pre-set.
<Communication speed setting (in Japanese)>

It shows the error rate when you set a speed other than the pre-set ones.
Note: It may have an error as the set parameter will be adjusted to the one which can be calculated by internal frequency divider.

Saves the communication data and time information

Saves the communication data and time information It can calcurate time stamps and idel times with high accuracy. It is not affected by the ability of PC regarding time accuracy while PC-based line monitors often suffer from it.

<Time stamp setting>


Line Monitor Function

It can monitor the communication data in real time without affecting the line. It can record the data with time stamps, idle times, and line status. You can switch the display to "line state display" and "display in each frame"


The Trigger Function Can Be Synchronized with External Signals.

The line monitor has a trigger function like the one the upper model has. Using the external trigger terminal you can do the analysis synchronizing with an external measurement device.

<Trigger condition setting>
<Trigger action setting>


Simulation Function

Seeing the monitor display you can transmit a pre-set fixed data or specific data by a screen touch.


Monitor Condition Auto Setting Function

This function offers an automatic configuration by assuming the communication condition from the monitoring process. It helps you to monitor the communication whose condition such as the speed is unknown.

Press where circled in red to start the analysis As the communication speeds of send line and receive line are separately analized and judged, it is useful for the troubles caused by a communciation condition diferrence.


Auto Backup Function

By the function the analyzer backup the latest about 30Kbyte data to the internal SRAM capture memory (battery powered) or all the data to a external USB memory connected with the line monitor.

<Auto backup serring>


PC Link

We offer a PC link software to display the monitored data or convert it to a text file on a PC. With the software you can remotely control the line monitor or update the firmware form the PC

Continuously Runs for 5 Hours by Batteries

It can continuously run for 5 hours by the attached two Ni-MH batteries. You can use alkaline battery too.

How it looks like when the battery room is uncovered.

USB Memory Supported

The measured data and configuration settings can be stored into a USB flash. You can save the former and the latter part of the target data by using the trigger setting. Also by making the Auto Backup function valid, it automatically saves all the measured data to a USB flash when it finishes the measurement.


Interface RS-232C, TTL(1.8V, 2.5V, 3.3V, 5V level)
Protocol ASYNC, UART
Capture Memory 16Mbyte (acout 4000Kdata), 2 part division is available
Speed (bps) 50, 75, 150, 300, 600, 1200, 2400, 4800, 9600, 12800, 14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800, user specified speed*1
Data length 7bit, 8bit
Parity bit NONE, EVEN, ODD
Stop bitƒg 1bit, 2bit
Error check Parity, framing, brake
Idle time Resolution 100ms, 10ms, 1ms, OFF(no display) can be selected. Max 999.9 seconds
Time stamp Date time stamp: Unit selectable among "Year/Mon/Day Hr:Min," "Mon/Day Hr:Min:Sec," "Day Hr:Min:Sec.10ms," or OFF (with no record)
Line state Records and displays the wave form and logical status of external trigger input and control line along with the transmission/reception data.
Data search Communication error, Max 8 characters data line (Don't care and bit maskare available)), idle time more than the specified duration, time stamp within the specified time range, cueing and counting of trigger matching data
Trigger function Up to four pairs of trigger conditions and actions can be specified.
Condition Communication error, communication data string up to 8 characters (don't care and bit mask are available), idle time more than the specified duration, Timer/counter match, logical status of the control line and external trigger.
Action Stops measurement/test (number of offsets until a stop can be set), validates trigger conditions, controls timer, controls counter, activates buzzer, saves monitor data into a USB flash, sends the specified character string, sends pulse output to external trigger terminal OT2
Monitor conditions auto setting Automatically configures the setting (max 460.8Kbps)*2
Simulation function*3 Test data transmission, ON/OFF of RTS/DTR
Only RS-232C port*4
Transmission data Max 16 (up to 16K in total) transmission data an be registered. 14 pre-set data and break output are available.
File management function Measured data and measurement condition can be saved into a USB flash and can be read from the USB flash.
Power save function Automatic light reduction, auto power off
Remote control PC link software (light version) is offered for free.
Line status LED Logical status of SD(TXD), RD(RXD), RTS, CTS are displayed.
Display 4.3 inch TFT color display (480x272dot)
Touch panel Capacitance touch panel
USB2.0 device port Micro B connector, high speed transmission supported. Used for PC connection and firmware update.
USB2.0 host port Standard A connector, high speed transmission supported. Used for USB flash connection*5
Power USB bus power 5V/500mA
Two AA Ni-MH batteries or two AA alkaline batteries (LR6)
Drive time*6 AA Ni-MH batteries: about 5 hours
AA alkaline batteries: about 2 hours
Temperature & humid 0 to 40 degrees celcius (-10 to 50 degrees celcius for storage), under 85%RH
Size & weight 158mm x 100mm x 31mm, 300g(including batteries)
Accesories DB9 branch monitor cable (LE-009M2), trigger I/O cable (LE-4TG), micro USB cable, two AA Ni-MH batteries, utility CD, carrying bag, quick start guide, warranty card
Product Model Remarks
USB charger LE-P1USB Used to provide bus-power to the line monitor or to charge Ni-MH batteries.
5 wires TTL prove cable LE-5LS The cable with IC clip can be connected with the TTL and external signal I/O port.
Monitor cable for DSUB25 pin LE-25M1 Used with the Dsub25-9 adapter when the target device has DSUB25 pin interface.
DSUB25-9 adapter LE-259AD2 DSUB25(female)-DSUB9(female) connector adapter. Can be connected to the RS-232C port of the line monitor to change it to DSUB25pin monitor port.
PC link soft LE-PC300R PC link software for Windows PC
Note: Ver1.05 or later is needed.
*1: User specified speed can have a margin of error.
*2: It cannot work properly when there are little communication data or when the data do not have 101,010 bit pattern.
*3: Only DTE mode is available
*4: The TTL port is for monitor only.
*5: Not all the USB falshes are supported.
*6: Based on our testing by common usage.