RENESAS TOOL NEWS
R20TS0474EJ0100 Rev.1.00 Page 1 of 5
Sep.16.19
[Notification]
Current Consumption Tuning Solution for RX and RL78 Families
Using E2 Emulator and QE for Current Consumption
Outline
This document provides an overview of the current consumption tuning solution for the RX and RL78
families.
This solution combines the E2 emulator and QE for Current Consumption and enables current
consumption measurement while running the program. Because measurement does not require a dedicated
measuring instrument or board modification, less time is required for preparing for tuning. Use this current
consumption tuning solution to reduce the time required for tuning the current consumption.
QE for Current Consumption (current consumption measurement tool) is a standard development support
tool built around the e
2
studio integrated development environment and CS+ (CS+ for CC only).
1. Current Consumption Tuning Solution
So far, debugging for low power consumption required repeated program corrections and verification
because the relationship between the current consumption and program is unclear. This solution has the
following three features to reduce the time required for tuning the current consumption.
1.1 Three Features
Easy to measure: The solution allows the current to be measured just with the E2 emulator and
QE for Current Consumption.
Additional measuring instruments or board modification is unnecessary. The current consumption of the
entire system can be measured easily just by connecting the E2 emulator to the user system and operating
QE for Current Consumption in the integrated development environment on a PC.
The figure below shows an example in which the E2 emulator is connected and the current consumption of
the entire system is shown in a waveform when the program is run and stopped. The current value at a
cursor position (red line in the computer screen) can be confirmed as with an ammeter.
R20TS0474EJ0100
Rev.1.00
Sep. 16, 2019
RENESAS TOOL NEWS
R20TS0474EJ0100 Rev.1.00 Page 2 of 5
Sep.16.19
Failsafe capture: Detect an abnormal current and stop the program.
By using the E2 emulator together with QE for Current Consumption, the program can be stopped based
on detection of a specified trigger condition (for example, an abnormal current increase or an infrequent
event). A current value or time can be specified for the trigger condition. This function allows for failsafe
capturing of abnormal current to aid in troubleshooting.
The figure below shows an example in which a current value (red dotted line) is set as a trigger condition
and the program is stopped when the trigger condition is met.
Find quickly: Visualize the relationship between the program and current.
The relationship between program operations and current consumption changes is visualized by setting
monitoring points in the program. Multiple monitoring points can be set in the program in the same way as
you set break points. This function allows the cause of current increases to be identified.
The figure below shows an example in which multiple monitoring points are set in the program and the
program is shown by double-clicking a monitoring point in which an abnormal current occurred.
1.2 Supported Devices
- RX family (RX100, RX200 series)
- RL78 family