User manual

Chapter 2 – Specifications
LT Series User Manual2–4
The LT unit’s internal clock has a slight degree of error in
accuracy. At normal operating temperatures and conditions,
and with the LT operating from its lithium battery, the degree
of error is ±65 seconds per month. Variations in operating
conditions and battery life can cause this error to vary from -
380 to +90 seconds per month. For systems where this de-
gree of error will be a problem, the user should monitor this
error and make adjustments as required.
1 A Lithium battery’s lifetime is:
• 10 years when the battery’s ambient temperature is under 40
o
C
• 4.1 years when the battery’s ambient temperature is under 50
o
C
• 1.5 years when the battery’s ambient temperature is under 60
o
C
When used for backup - assuming 96 hours (4 days) to charge fully:
• Approximately 60 days with a fully-charged battery
• Approximately 6 days with a half-charged battery
 Serial Interface for Type C and Tool Connector (All Types)
Application
1 MB FLASH EPROM (Approx. 320 screens at 3.2 KB/screen)
Data Backup
96 KB SRAM (uses lithium battery)
*1
Clock Accuracy
±65 seconds/month (at room temperature)
Variable Area
32 KB SRAM (uses lithium battery)
*1
Program Area
128 KB FLASH EPROM
2.2.2 Memory
2.2.3 Control Memory
2.2.4 Clock
2.2.5 External Interfaces
Serial Interface
Asynchronous Transmission:
RS-232C or RS-422
Data Length: 7 or 8 bits
Stop Bit: 1 or 2 bits
Parity: None, Odd, or Even
Data Transmission Speed: 2400 bps to 115.2 kbps
Tool Connector
Asynchronous TTL level nonprocedural command I/F
During Screen File (HMI interface) Development:
• used to transfer data between the LT application software/
C-Package and the LT unit
During Operation:
• used for a variety of devices, including a bar-code reader