Incorrect HEX conversion
If your source file is in HEX, you may need to specify an offset to get a proper conversion. If an offset is
required, it is usually the starting address of the EPROM. You can use RTDUMP16, RTDUMP32 or
Quickloader to see where the conversion placed the binary data within the device space.
Failed to split the file between emulators
If you want the command line loader to spilt the file between multiple emulators, you need to specify a /Ex
parameter to tell the loader how many emulators to split the file between. In Quickloader, you must specify
the ‘number of emulators’.
File loaded into the wrong emulator(s)
If you have 2 or more emulators daisy-chained, you may have loaded the file into the wrong unit(s). Watch
the STATUS LEDs to see which units where actually selected for the transfer. The loaders default to
emulator #1. To select a different emulator, specify a /Fx parameter. This tells the load the FIRST
emulator involved in the transfer.
Incorrect Byte Order
If you are loading into multiple emulators with automatic splitting, remember that the loader will load the
FIRST byte in the file into the lowest numbered emulator involved in the transfer. If the emulators are
plugged into the wrong target sockets, you can move them to the correct sockets or you can change the
order in which the emulators are daisy-chained.
Target Power noisy or Voltage too low.
Noise problems are very dynamic. It is possible that we could load and verify OK, but as soon as we release
reset and let the target start running, system noise increases and trashes the system. Low system voltage
could behave in a similar manner. It is possible that we could load and verify with a target voltage that is
well under spec, but the target will not execute properly. FlexROM III draws more current than the EPROM
it is replacing. The target may be able to supply enough current during downloads, but may not be able to
hold the voltage up when it starts running, causing power fluctuations or noise.
Emulator too slow
FlexROM IIIs are rated at 45ns. The emulator must be at least as fast as the access times required by the
target (smaller numbers are faster). If the target’s access requirements are not documented, you can get a
general idea of its requirements by looking at the EPROM’s rating. The EPROM’s speed is not an absolute
indicator because many EPROMs run faster than they are marked; particularly at full voltage and room
temperature. We have seen many systems that appear to run fine, even though their access times routinely
violate the EPROM’s rating. Fortunately, FlexROM III’s speed rating (45ns) is faster than most ERPOMs
used in embedded systems.
If your target’s access time specs require a faster emulator, look at FAST OE and FAST CS options
described in the ‘Configurable Timing Parameters” section. One or both of these options may allow you to
relax the target’s access timing requirements and bring them within the emulator’s specs.
Noisy Control Signals
Try enabling control line filtering or increasing the amount of filtering. See the “Configurable Timing
Parameters” section for details.
Noisy Address Lines
Look at the Latching Options described in the “Configurable Timing Parameters” section.
FlexROM III User’s Manual
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