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Frequently asked questions

LPC2000 Family Tools FAQ

Q How many hardware breakpoints can be used without using the RAM?
A The ARM Embedded ICE unit only allows 2 hardware breakpoints.
Q What is the ETM trace depth?
A The ETM version we use has a 10 byte FIFO (Address trace only).
Q What about RTOS support for LPC210x?
A
The following RTOSes support the LPC210x:
  • MicroCOS2 (by Micrium ltd.)
  • CMX (CMX Systems)
  • ThreadX and Integrity- (By Green Hills Software)
  • Nucleus (Accelerated Technology)
Debuggers like Nohau's Seehau and IAR's C-SPY debuggers have plug- ins for the MicroC-OS2.
See our Development Tools sections for additional tools.
Q In the LPC2104/5/6, when I enter debug mode, port pins 22-31 are not useable by the application even though I am using JTAG for debugging which uses only 5 pins. What's happening?
A
What you are experiencing is correct. In primary debug mode, the port pins 22-31 are configured for trace even if you are only using JTAG. If you wish to use only JTAG while debugging and your application needs additional port pins, then use the secondary JTAG interface. In this interface, port pins 27-31 are used for debugging purposes and all other pins can be used by the application. An application note is available which provides detailed instructions as to how to use this interface.
Q I'm using the MCB2103, and I'm having problems running code at 70MHz. I'm also having trouble running at 40-60MHz if my peripherals are running at the same speed or even at half the speed of the core. What could be causing this?
A
There is a known problem with the first revision of the LPC2103. Under increased power consumption conditions, the device may not operate properly. The likelihood of the problem increases as the device is run at higher speeds (approaching 70MHz) and/or if the peripherals are running at close to system frequency speed (i.e., if the APBDIV register is set to less than 4 meaning the peripherals are running faster than 1/4 of the system frequency). To resolve this, run the LPC2103 core and/or peripherals at lower speeds or increase the voltage on Vdd1V8 by replacing the 1.8V regulator with a 2.0V regulator. This information is also contained in the LPC2101/LPC21012/LPC21013 errata sheet.
Q I'm using the MCB2103, and I'm having problems with using P0.17 and P0.18 as GPIO. The ports appear stuck low (LEDs on MCB2103 always off). I can't write 1s to the ports and the blinky examples don't toggle these pins either. I traced through the hardware and found nothing wrong. What could be causing this?
A
The current user manual for the LPC2103 states that these pins (P0.17 and P0.18) are always "open drain". If you need to use them as outputs and drive them HIGH, then you can add two pull-up resistors (e.g. 10KΩ) to these pins, connecting them to 3.3V.
Q While using the Keil Software USB examples on the MCB2140 board, the USB LED does not work and the examples do not pass the USBCV tests. What could be wrong?
A
On some MCB2140 boards produced in November 2005, the resistor values R39 and R38 were reversed. Make sure that the value of R39 is 10KΩ and R38 is 100KΩ as stated in the MCB2140 schematics available on the Keil Software MCB2140 Evaluation Board page.
Also make sure that you are using the current versions of the USB example projects available under:
Q Are there any free tools for flash programming of LPC2000 devices?
A
NXP has partnered with Embedded Systems Academy to provide a free tool for flash programming called Flash Magic. Flash Magic is available for free download. It supports the entire LPC2000 family (except LPC288x).
NXP also provides one more tool for flash programming which supports some of the LPC2000 devices (called LPC2000 Flash ISP Utility v2.2.3). However, it is recommended to use Flash Magic instead since no new updates will be carried out in this software beyond v2.2.3.
Q Is Linux ported to the LPC family?
A
μCLinux is ported to the LPC2000 family, and Linux 2.6.10 is ported to the LPC3180 ARM9 device.
Q Is Windows CE ported to the LPC2000?
A No. Not currently.
Q Is there any parallel programming support for the LPC2000 family?
A Yes. Vendors which provide support for this option include: BP Microsystems, HI-LO systems, Xeltek, System General, and Data IO.
Q Do we have IBIS models for the LPC2000 family?
A
We have models available for most LPC2000 devices.
Q Is Boundary Scan available on the LPC2000?
A
LPC23xx, LPC24xx, and LPC29xx devices are the only LPC2000 devices that have Boundary Scan implemented. BSDL files are available for free download on the Standard ICs website.
Q When the LPC2468 BSDL (Boundary Scan Description Language) file is compiled, why does an error occur on the I2C pins (P0.27 and P0.28)?
A
Various BSDL tools compile I2C pins (open collector pins) differently. Some tools expect the disable value of these pins to be "WEAK1"; others expect it to be "Z".
In the BSDL files for LPC23xx/24xx family, the disable value of these pins are defined as "Z":
LINE 544 "265 (BC_2, P0_28, output2, 1, 265, 1, Z), " &
...
LINE 548 "261 (BC_2, P0_27, output2, 1, 261, 1, Z), " &
If a compile error occurs, please modifiy the lines as shown below and recompile:
LINE 544 "265 (BC_2, P0_28, output2, 1, 265, 1, WEAK1), " &
...
LINE 548 "261 (BC_2, P0_27, output2, 1, 261, 1, WEAK1), " &

Other Questions

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