Subject: Program Development Link - Comments I just received the Program Development Link ver 1.0 in the mail. I have spent the last two days playing with it and offer this review to those who might be interested in purchasing the product. Disclaimer: I do not work for HP or am I in any way affiliated with their advertisement of testing of their products... I just like their calculators. HP Program Development Link for the HP48 --- Comments The Program Development Link(PDL) is a menu driven software application for the IBM-PC/AT that allow you write HP48 applications with the PDL editor( or your favorite editor), transfer the applications to your HP48, and test them on the HP48 all from the comfort of you IBM-PC/AT keyboard. An HP48 application is defined as a set of programs and variables that work together to perform a function. The PDL features a built in editor that does `automatic' character translations from translation code 3 sequences to the nearest IBM character equivalents. One can enter lines of code in either the TC3 format or pick special characters off of a top line menu bar. Common TC3 sequences, i.e. \<<,\>>,\->, do not need the leading `\' to be translated. Code can be entered in lowercase with HP48 commands converted to uppercase. Conversion to uppercase and TC3 translation all take place when you type carriage return. Applications are saved on disk in a new format-- PDL( of course). This format is in essence identical to TC3 except for some important differences. PDL format consist of a few special control sequences. A control sequence is characterized by a `\' as the first character on the line. Anything following that is interpreted as a control sequence by the PDL. '\\' indicates a PDL comment. PDL uses this format almost exclusively. The PDL program is structured to operate in, out and around this format. This in it self is not bad. PDL does this very well. I found that the structure the package sets up is quite efficient and effective. I wrote a few short applications as a test and loved it. Creating, editing, and testing of code is a breeze. However editing of code not in PDL format is a chore. When PDL send code TO the HP48 it automatically translates PDL format into TC3. But PDL has no way of translating TC3 directly into PDL. In other words say you have a directory object on the HP48 which you would like to upgrade with PDL. You CANNOT simply read the directory object into PDL an edit it using PDL full potential. You can read the entire object in as a single variable. But this is essentially the same using an editor( only worse because the PDL editor is slow). The only way to convert plain vanilla TC3 into PDL format is to `manually' insert the appropriate `\` sequences into the code and delete the unnecessary `DIR''s and `END''s. This can be a bit of a hassle for a large directory object. I am a little disappointed that HP could not have included a little filter program to convert TC3 to PDL format. The conversion process is fairly easily. A short C program would do the trick. I am writing one now and should be finished in a week or so. The HP48 Immediate window is handy. It allows you to run your HP48 programs from the PC and see the results on the PC screen. PDL includes with it a HP48 library of special programs that allow for this high level of machine interaction. The library can be install in the HP48 (called Enhanced Transfer by PDL ) or the relevant programs are transferred to, executed and purged on the HP48 as they are needed. The latter process is as you might expect much slower than having the library resident on the HP48. Overall I think that the Program Development Link is a useful software package to have. I have only a couple minor complaints. First the package is slow. I operate on an IBM-AT and PDL seems to lack behind in responding to keystrokes for moving between lines, both in the editor and in menus. It think this is due to two reason. The first has to do with automatic character translation. PDL has to process each line to convert TC3 into IBM equivalents. This feature can be turned off and the package speeds up considerably. But there are consequences. When character translation does not take place, it does not take place. For example if you want to create a variable, say `R\- >D' you can type `R->D' at in the `variable name' field and with character translation ON the sequence is translated correctly to TC3 when sent to the HP48. But when character translation is off `R->D' is translated verbatim and transferring to the HP48 crashes with an "illegal name" error. One can FORCE character translation however by typing 'R\->D' at the field prompt. The second reason the package may be slow has to do with the use of the keyboard for selecting menus. PDL allows you to use either the keyboard or a mouse for selecting, pointing, moving etc. Since I am still 'out of style' in using a keyboard this problem is probably 'my fault' :-). My second complaint is the lack of a filter for TC3. One of my principle motivations to purchase the PDL package was to update directories in my HP48 easily. After receiving the package I was disappointed that there was no direct convert TC3 into PDL format. I was annoyed, after comparing the two formats and finding that the differences were trivial. But I will not just complain unconstructively. As I said before, I am writing a program now to do the conversion. I will post it as soon as I am satisfied with it. There are a number of other handy little features PDL has that I have not mentioned. Things like the excellent help utilities, the ability to transfer only the modified variables of an application, etc. I am sure there are still a few B's to be worked out with PDL aside from the complaints above. But for Ver 1.0 it looks pretty good so far. I have only used it for two days and already wondered how I could have tolerated writing large code with the HP48 keyboard. I am happy with the product. -- -------------------------- james dixson dixson@astro.utexas.edu