PROMJet is one of the worlds most advanced memory emualtors. We do not know of any other memory emulator that offers this kind of features at this physical size or price. This page discusses the features of PROMJet and how it compares to other emulators. This helps the customer make the right decision when buying new memory emulators.

PROMJet Firsts:

Since its introduction in 1993, PROMJet had a lot of firsts. At the time of its introduction, most of the emulators in the market had the 80s style look (a box with cables to connect to the target system). At this point PROMJet had a PCB size of 1.6 x 1.9" and the same footprint as a DIP FLASH memory. It used dual-sided surface-mounted FPGA chips to replace 100's of TTL parts used in other emulators. It also had then the fastest transfer speed of 1.2 Mbit/Sec. It did not have all the features of the current PROMJet or the capacity of it, but it was still the most advanced product in the market at the time. Below we will present some feature PROMJet introduced first.

More then one company have tried to develop a similar emulator. Professional look was not the only thing missing their emulator. They all lacked a lot of features that PROMJet offered such as debugger integration, emulated memory size/speed, dual-ported memory access, stability and reliability. Also quite a number of companies have tried to develop a dual-ported memory solution similar to PROMJet but FAILD and ended up with either a lesser featured emulator or quitting the memory emulator market leaving their customers with no support.

Below are some features that EmuTec has put together to show the difference between PROMJet and other emulators in the market. We encourage you to check for these features with all vendors you are considering before making a decision. It will save you a lot of time when developing your code!!!.

1. Transfer speed. PROMJet download speed from host to target is twice as fast as the next fastest emulator in the market that we know of. It has a minimum speed of 1.6Mb/S. Some emulator companies claim their emulator has a transfer speed of 2.5Mb/S. The user gets only 400Kb/S and they claim it on the printer port type and mode.
2. Access time. PROMJet has the fastest access time in the industry (20ns). It plugs directly into target socket for less capacitive load to the CPU bus and minimal intrusion effects. Most of the emulators use flat ribbon cables, which have high capacitive load, to connect to the target CPU!!!.
3. Byte/Word access. PROMJet can support 16 and 8-bit devices from a single unit at full capacity (e.g. 2Mx8b or 1Mx16b). The unit is software switch-able and works in both modes at full access speed. There is no need for external cards or adapters to support one mode or another. Some 16-bit emulators can only work in 8-bit mode at half capacity (by just ignoring the high data lines).
4. On-the-Fly accesses. With the ICE option, you can access memory on the fly without the need for arbitration circuits as with other emulators. Some companies have tried and failed to deliver such a feature. Be aware of all the claims other companies make.
5. Virtual Communication Channel. Debugger support for some emulators is done with two cables. One for speedy download (parallel) and one for debugger communications (Serial). PROMJet uses only one connection (parallel or Ethernet) to satisfy both. Some companies claim they can do the same!!!.
6. Trigger/Trace. PROMJet has adapters that connect it to an HP or Tektronix logic analyzer to record trace information. Also it has a single built-in hardware watch-point. Some other emulators provide a trace engine that just dumps accessed memory locations in a text file. The user has then to search the file to see if an address has been accessed or not. This method, even though is easy to develop, consumes a lot of reconstruction time since the user has to go through the MAP file to see the CODE executed!!!.
7. Technology. PROMJet uses newer technology based on FPGA with extremely low leakage current. Other emulators use decade-old TTL technology that loads the target bus.
8. Noise. PROMJet has built-in noise reduction circuits that reduce the target board noise. Most of the emulators in the market do not have these circuits.
9. Variable Voltage. Low voltage support is done inside PROMJet. In the case of other emulators you must have an external adapter that adds about 15ns of delay to the emulator access time. A single PROMJet with variable voltage option supports targets with Vcc between 1.8 and 5V without the need to plug any external adapters.
10. Ethernet support. PROMJet Ethernet adapter is custom made for PROMJet. Some emulators use a standard Ethernet print server to interface their emulator to Ethernet. We have seen customers with hang-ups between the emulator and the Ethernet server. Support is also a problem since they do not own the hard or firmware inside the server. Also some companies use an Ethernet-Serial adapter and connect the serial cable to link the adapter to their emulator!!!. This method decreases the transfer speed since all data has to go through a serial link (56Kbit).
11. Software. PROMJet has NATIVE Windows 9x/NT/2000 and DOS software. Some emulators claim to have Windows software but they only have DOS software that runs in a DOS window under 9x/NT. We have seen a lot of customers with time-out problems using this solution.