P&E Microcomputer Systems USB Multilink ACP User manual

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P&E Microcomputer Systems, Inc.
www.pemicro.com
Technical Summary for
USB Multilink ACP, Rev. B (PART# USB-ML-ACP)
Support for ARM Cortex processors (complete list at pemicro.com/arm)
Document# PE3514, Version 1.04
1. Introduction
2. Device Support
3. Debug Headers
4. Usage
5. Driver Installation
6. Connecting To The Target
7. Troubleshooting
8. Interface Libraries
9. Third-Party IDEs & Other Compatible Software
10.Transition To Production Programming
1 Introduction
The USB Multilink ACP is a low-cost debug interface supporting a wide range of ARM Cortex processors. The Multilink provides
access to debug modes by communicating between the target device and a laptop/PC via the target's standard debug header
and a laptop/PC's USB port.
2 Device Support
Multilink ACP supports ARM Cortex-M devices from these manufacturers:
· NXP · Redpine Signals
· Cypress Semiconductor · Silergy TeridianSilicon Labs
· Infineon · Silicon Labs
· Maxim Integrated · STMicroelectronics
· Microchp (Atmel) · Texas Instruments
· Nordic Semiconductor · Toshiba
· OnBright · WizNET
For a complete listing of supported ARM Cortex-M devices or to request support for a device, visit PEmicro at:
http://www.pemicro.com/arm
3 Debug Headers
Three standard ARM headers are located inside the unit. Port A is a dual-row header with a .100" pitch, while Ports B-C are
dual-row with a .050" pitch.
USB Multilink ACP Debug Probe

USB Multilink ACP - Technical Summary
Multilink ACP Pin-Outs, Ports A, B, C
The user can take advantage of debug modes to halt normal processor execution and use a computer to control the processor.
The user can then directly control the target's execution, read/write registers and memory values, debug code on the processor,
and program internal or external FLASH memory devices.
4 Usage
The USB Multilink ACP can communicate with ARM Cortex microprocessors by connecting a ribbon cable between the target's
debug header and one of the multiple ports on the Multilink. Do not attempt to use multiple ports at once, as this may damage
both the target processors as well as the Multilink.
The USB Multilink ACP interfaces will work with targets whose processor power supply is in the range of 1.8V to 5V.
Multilink ACP Header Layout (Pin 1 Highlighted)
There are two LEDs on the Multilink interface. The blue LED indicates that the interface is powered and running. The yellow
LED indicates that target power has been detected.
Note: To avoid improper connections, the red stripe of the ribbon cable should always be oriented towards Pin 1, both on the
Multilink port and the target processor header.
The USB Multilink ACP is a USB device. If a USB Hub is used, it must be a self-powered hub (i.e. with its own power supply). By
default, the USB protocol used is USB 2.0.

USB Multilink ACP - Technical Summary
5 Driver Installation
Before connecting the Multilink to the PC, the appropriate drivers need to be installed on the PC. The Multilink drivers are
supported on Windows XP, 2000, 2003, Vista, 7, 8, and 10. These drivers are automatically installed when installing NXP’s
CodeWarrior or any of PEmicro’s recent software development packages. If you have installed a recent version of these then
the instructions for manual installation that follow are not necessary. However, Windows 7 users who are installing software
distributed before December 28, 2009 will need to obtain the latest version of the drivers and install them manually. A copy of
the driver installation program may be downloaded from the “Downloads” section of PEmicro’s “Support Center” located at http:/
/www.pemicro.com. If you are using third-party software, make sure you have a version which supports your specific interface
(Multilink ACP). Once you have obtained the latest version of the driver installation program, please use the instructions below
to manually install the drivers.
When the cable is plugged in, the operating system should indicate that it has found a driver for the attached interface. Follow
the instructions in the “Found New Hardware Wizard” dialog for having Windows automatically install the driver.
If you connected the Multilink interface prior to installing the drivers, Windows will not have been able to find the appropriate
driver and may have disabled the device. If you unplug the device and then plug it in again, Windows will automatically disable
it even if you have installed the drivers. To force Windows to attempt to load the driver again, perform the following steps while
the Multilink interface is plugged into the computer:
1. Open the Control Panel: Start Button [ ->Settings ] ->Control Panel. (You will not need to select “Settings” on Vista and Win-
dows 7).
2. Double Click the “System” Icon. (Windows 7: “System and Security”)
3. Select the “Hardware” Tab. (Windows 7: “Hardware and Sound”, Windows Vista: skip this step)
4. Click the “Device Manager” Button. (Windows 7: “Devices and Printers -> Device Manager”)
5. The “USB Multilink 2.0” device will be shown with an exclamation point next to it. Double-click this device.
6. Click the “Reinstall Driver…” button and follow the dialog instructions to have Windows automatically install the driver. (Win-
dows 7: First click the “Driver” tab, then select “Update Driver...”)
7. If the hardware still has a yellow exclamation mark next to it, right click on it and select uninstall. The USB Multilink should
disappear from the list. Unplug the USB Multilink and then plug it into the PC again. A new Hardware Found dialog will pop
up; follow the dialog instructions and have Windows automatically install the driver.
6 Connecting To The Target
The following is the proper connection sequence to connect the PC to the target system via the Multilink interface:
1. Make sure the target power is OFF and the USB Multilink ACP is not connected to either the target or the PC
2. Open the Multilink and connect a ribbon cable from the correct Multilink port to the target. Make sure that the ribbon cable
is plugged into the target with the proper orientation. PIN 1 is indicated by a 1 next to the port.
3. Connect the Multilink to the PC via a USB cable. The Blue LED on the Multilink should illuminate.
4. Turn the target power on. The Yellow LED on the Multilink should illuminate.
Before disconnecting the setup, turn the target power off.
7 Troubleshooting
Note that if the Multilink does not enter debug mode, the program issues the error message "Cannot enter background mode."
If you receive this message you should check your hardware with a scope, logic analyzer or logic probe.
1. Check that the board is powered on. The voltage value of the TVCC pin on the header should equal the logic high value -
usually 3.3V or 5V.
2. Monitor the activity of the debug signals:
JTAG: TCK, TDI and TDO
SWD: SWD_CLK and SWD_DIO
During correct operations, these signals will toggle between GND and logic high voltage levels. Look out for signals that do
not toggle or do not fully transition all the way to GND or logic high.
3. Disconnect the Multilink ribbon cable from the board. Power on the board and monitor the RESET signal on the header.
Normally this signal should be high or toggling due to a watchdog. Look out for a situation where the RESET signal is per-
manently low.
8 Interface Libraries
PEmicro produces a set of interface libraries which allow the user to directly control the USB Multilink ACP from any Windows
Development environment which can interact with a DLL. The interface libraries come with examples for controlling the Multilink
interface from Microsoft Visual C as well as Borland Delphi. More details can be found on the Interface Libraries page on the

USB Multilink ACP - Technical Summary
PEmicro website: http://www.pemicro.com/products/product_processor.cfm?category=9
9 Third-Party IDEs & Other Compatible Software
The USB Multilink ACP is supported by recent versions of NXP’s MCUXpresso, CodeWarrior, Kinetis Design Studio, S32
Design Studio, STM32CubeIDE, and DAVE IDE, as well as third-party toolchains such as those from IAR, Keil, Silicon Labs.
Cosmic, and Mentor Graphics. A list of third party ARM IDEs can be found at:
http://www.pemicro.com/arm/3rd-party/index.cfm
Multilinks also work with PEmicro software, including our no-cost, fully-featured GDB Server Plug-in for Eclipse-based ARM
IDEs.
It is recommended that you check with the vendor regarding support for your specific part. Information on compatible PEmicro
software can be found in the “Products” section of PEmicro’s website: pemicro.com.
10 Transition To Production Programming
The USB Multilink ACP is intended for development and is not designed
to accommodate the demands of production programming. However,
PEmicro’s Cyclone LC and Cyclone FX programmers are specifically
engineered to withstand the rigors of a production environment and will
provide a seamless transition from the Multilink. Both include PEmicro’s
Cyclone Control Suite for Cyclone control and automation. In addition,
Cyclone FX programmers offer an extended feature set including larger
internal storage, expandable storage, faster communications, enhanced
security, advanced Cyclone Control Suite features, and extension
ports.More information is available online at pemicro.com/cyclone.
Cyclone Programmer