VCMA9 Frequently Asked Questions

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Question #340: I observe power-up problems or sudden, unmotivated resets of the MIP board during normal operation. It seems to get worse if an additional add-on card is installed and/or the CPU and/or GPU load is increased.
Answer: Chances are that this is a power supply problem. In contrast to the PIP boards, the MIP boards expect their 5V system input voltage to be provided in a "suitable, clean" form, especially relating to short power transients. Please check the following points:

  • make sure there is a low impedance connection between the external power supply and the MIP board (wire length as short as possible / wire cross section as wide as possible).
  • supply 5.25V  instead of 5V to the system.
  • use a better power supply.
  • solder the power supply wires directly to the pads of the power supply connector on the MIP board.


Question #345: I'm having trouble to get an USB device to work with one of your SBC. Either the USB device is not working reliable (or not at all) or the MPL SBC is even being reset if I insert the plug into the USB port or if the device is activated. The same USB device works without problem if I connect it to my laptop/desktop.
Answer: Is the USB device powered from the USB port only (no external power supply is being used)? If yes, your USB device most probably needs more power than it is allowed to do. The USB standard specifies that an USB device must not consume more than 500mA for USB2.0 / 900mA for USB3.0 (even not more than 100mA before being successfully initialized). For all USB peripherals with higher power requirements than the values mentioned above, the use of an external power supply is mandatory.
So please make sure that you use an external power supply or try to find another, standard conforming USB device.

Please note that the use of an "Y" shaped USB cable to "steal" power from a second, unused USB port is NOT a solution!

Question #230: What OS support is available for the VCMA9?
Answer: Currently we can offer Board Support Packages (BSP) for the following OS:
  • Linux (based on Kernel 2.6.15)
  • Windows CE.NET V4.2

Question #235: What SDRAM sizes are possible on the VCMA9?
Answer: Actual following SDRAM sizes are possible: 32MByte, 64MByte and 128MByte. The SDRAM interface on the VCMA9 is 32bit wide! Our standard products are equipped as follows:
  • VCMA9-41 has 64MB SDRAM
  • VCMA9-55 has 128MB SDRAM

Question #234: What NAND flash sizes are possible on the VCMA9?
Answer: Actual following NAND flash sizes are possible: 8MByte, 16MByte, 32MByte, 64MByte and 128MByte. Our standard products are equipped as follows:
  • VCMA9-41 has 8MB NAND flash
  • VCMA9-55 has 128MB NAND flash

Question #231: How can I see the U-Boot bootloader messages?
Answer: Normally (default) the U-Boot bootloader on the VCMA9 board uses serial line 0 (connector J2) as its console device (for input and output). The parameters of this serial communication are set by default to:
  • 9600 baud
  • 8 bits
  • no parity
  • 1 stop bit
  • no handshake
Please use a so called "null modem" or "crossed" cable to get a working communication link.

Question #236: What LCD's are supported on the VCMA9?
Answer: The LCD controller on the VCMA9 supports TFT as well as STN LCD displays. Further maximum 16M colors are possible and multiple screen sizes are supported (e.g. 640x480, 320x240, 160x160 and others). The maximum virtual screen size is 4Mbytes.

Question #232: How do I get the maximum 64 digital I/O's?
Answer: By using different CPU internal multiplexed pins as digital I/O instead of there other interface function. The configuration of this multiplexed pins is done by the bootlaoder and can be changed according your requirements. For more information about the digital I/O's on the VCMA9 please see the documentation "Digital I/Os on VCMA9.pdf".

Question #233: What function/peripheral interface do I lose if I need more than 8 digital I/O's?
Answer: Depending on how many digital I/O's you need, you may lose following interfaces: I2S, SD, Timer, SPI1, Touch and/or LCD-signals. For further information please see the documentation "Digital I/Os on VCMA9.pdf".
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