Tom, I was a Rockwell applications engineer for seven years in the Santa Clara, CA before I retired in January and I am very familiar with 224ATL.
Joe is correct the RC224ATL was intended to be used in North America, Australia and Japan. The dial-tone and Busy-tone cadence detection are not correct for a Netherlands design. Since it is a canned solution there is no way to change the cadence detection. If you want to stick with Rockwell as a supplier I suggestion you use the RC229ATF2W, RC2324AC2W (these are two chip sets). If you can write code use the RC2324DPL (a pump) which requires a controller, of your choice, you will have to write the code. I don't advise doing this if you haven't done it before. The code legal issues involving Hayes, and others is painful. It is best to use a vendor with a solution that has taken care of legal issues before they supply you chips. If you start the circuit and PWB design with most of Europe in mind, it would be easy to support most Euro countries in the future. By using ConfigurACE the code could be tailored for each easily and with hardware changes limited to loading or not loading certain parts. The last time I checked Rockwell's world wide code supported 36 countries. Just like Joe I'm contracting and consulting on modem and telephony designs. In case you don't know Joe Randolph, he has as much experience with Euro designs as anyone. My 27 yrs of modem experience has been APAC, North America and South America. I suggest you contact Howard Hathaway in the Rockwell Aus. office and tell him, his Dad said he wasn't taking very good care of you. Dad is a private joke between Howard and myself. He'll get a laugh out of out it. His tel number is 805-5555. I'm surprised Rockwell let you get this far with a design that wouldn't work from the start. Regards, Duane On Wed, 15 May 1996 [email protected] wrote: > In a message dated 96-05-15 20:10:29 EDT, you write: > > >Our company is going through the growing pains of its first modem > >design with intended sale in Europe starting with the Netherlands. We > >have choosen the Rockwell RC224ATL modem chip and our first run > >through of our design indicates some weak points, (ie possible > >problems) in the dialtone and busytone detection areas. > > > > Tom: > > I looked at the Rockwell RC224ATL chip about two years ago for an embedded > modem application that had to meet worldwide approval requirements. At that > time, my conclusion was that this device did not offer sufficient flexibility > in the call progress tone detector. > > I believe the part was designed for the North American market, and the call > progress tone detectors are hard-coded to detect North American tones. You > may find that this part works OK in countries where the call progress tones > and the cadences are similar to North America, but I do not think this part > is a good choice if you plan to sell your product worldwide. > > In general, a call progress tone detector for worldwide applications should > allow you to configure the allowable frequency bandwidth, cadence, and energy > threshold for the tones that you are trying to detect. > > At the time of my investigation, the least expensive Rockwell solution that > had the required flexibility was the RC2424DP/1. I ended up using a general > purpose DSP instead, so I can't say much more about the RC2424DP/1 except > that it appeared to have the required flexibility. I do not know if Rockwell > even sells this chip any more. > > In general, I believe that Rockwell sells their modem chips in two > categories. The first type is a "data pump" that implements the basic modem > functions and usually offers direct access to the coefficients of the tone > detection filters. These devices offer maximum flexibility, but you must add > your own microprocessor that implements higher level functions such as the AT > command set, data compression, and error correction. > > The second type is a pre-packaged version that uses one of Rockwell's > microprocessors to implement the high level functions. In this second > category, the call progress tone detection parameters are usually hard-coded. > However, for some members of this family, Rockwell offers a software utility > called "ConfigurACE" that lets you modify the parameters used in the call > progress tone detector. > > So, I suggest that you have a detailed discussion with a knowledgeable > Rockwell applications engineer, to make sure that the specific Rockwell > device you select has the flexibility to accommodate the countries that you > wish to cover. > > > Joe Randolph > Telecom Design Consultant > Randolph Telecom, Inc. > >
