J-Link / J-Trace User Guide (UM08001) - Microcontrollers

32 CHAPTER 1 Introduction
Clock fall time (T fc ) Max. 10ns
1.3.7.3 Download speed
The following table lists performance values (Kbytes/s) for writing to memory (RAM):
The actual speed depends on various factors, such as JTAG, clock speed, host CPU
core etc.
1.3.7.4 Hardware versions
Version 2
Obsolete.
Version 3.1
Trace Interface, Electrical
Power supply
USB powered
Max. 50mA + Target Supply current.
Target interface voltage (VIF ) 1.2V ... 5V
Voltage interface low pulse (VIL ) Max. 40% of VIF Voltage interface high pulse (VIH ) Min. 60% of VIF Trace Interface, Timing
TRACECLK low pulse width (Twl ) Min. 2ns
TRACECLK high pulse width (Twh ) Min. 2ns
Data rise time (Trd ) Max. 3ns
Data fall time (Tfd ) Max. 3ns
Clock rise time (Trc) Max. 3ns
Clock fall time (Tfc) Max. 3ns
Data setup time (Ts) Min. 3ns
Data hold time (Th ) Min. 2ns
Table 1.8: J-Trace for Cortex-M3 specifications
Hardware Cortex-M3
J-Trace for Cortex-M3 V2
190 Kbytes/s (12MHz SWD)
760 KB/s (12 MHz JTAG)
J-Trace for Cortex-M3 V3.1
190 Kbytes/s (12MHz SWD)
1440 KB/s (25 MHz JTAG)
Table 1.9: Download speed differences between hardware revisions
Identical to version 2.0 with the following exceptions:
• Hi-Speed USB
• Voltage range for trace signals extended to 1.2 - 3.3 V
• Higher download speed
J-Link / J-Trace (UM08001) © 2004-2010 SEGGER Microcontroller GmbH & Co. KG