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HP Forum Archive 14

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several ways downloading SW to 48S/GX?
Message #1 Posted by Valentino Ducati on 5 Dec 2004, 5:27 p.m.

Hi all

I'm a 48 newbe, working for years with the 41. I read very much about th 48 series in the last days (manuals, and many other internet sources) but I didn't find the following: What are the several ways of downloading a program to a 48? Which are the file format 48 SW can be stored?

Please have a look here at There are 6 (six!) ways and many formats to input a program into a 41. And they are all well explained. And, if you fail with all other you have still #6: Keyboard input! (And there are more, if you had the card reader of HP-IL...)

Now to the 48 series. Having (yet) no cable I found a program to enhance the IR port to connect with PCs. But here begins the problem: It seems no more usual to print the program listing to the internet (even if it is only User/SysRPL). That leads to the further problem, that I have no chance to use any of the many programs in the internet, because it seems only to exist one way: PC -> connection SW -> CABLE -> hp48.

Or did I miss something? Please help.

Re: several ways downloading SW to 48S/GX?
Message #2 Posted by Jonathan Purvis (New Zealand) on 5 Dec 2004, 6:01 p.m.,
in response to message #1 by Valentino Ducati

Cables for the 48 are easy to build. The connector has 2mm pin spacing, rather than the usual 0.1", but they are often found in CD-ROM audio cables and serial mice.

There are 2 types of file for the 48. ASCII ones are User-RPL souce code and have a header similar to "%%HP: T(3)A(D)F(.);" (specifying the level of character to \ escape sequences, angle mode and fraction mode). Binary files have a header of "HPHP48-A" where the "A" is the ROM version (A-J for 48S series and K-R for 48G series).

The only ways to get files onto a 48 are RS-232 cable, IR, memory card (for the SX and GX) and typing it in. If you really want to type in a program that you only have as a binary version, you could use Bill Wickes' ASC program, which converts programs to hexidecimal strings. It comes with a User-RPL decoder and ASC'd Sys-RPL decoder/encoder and is in the comp.sys.hp48 FAQ and at There is a MS-DOS program to do the same at

Re: several ways downloading SW to 48S/GX?
Message #3 Posted by Ed Look on 5 Dec 2004, 7:24 p.m.,
in response to message #1 by Valentino Ducati

As far as I know, you are right. The 48 series machines can only be accessed for communication via cable.

My recommendation is to buy one; I made one once, and it was hard to use (and just a few days ago, the connector fell off the cable). The commerical one is more robust and easier to use.

Re: several ways downloading SW to 48S/GX?
Message #4 Posted by James M. Prange on 6 Dec 2004, 4:08 a.m.,
in response to message #1 by Valentino Ducati

All 48 and 49 series work with the Kermit File Transfer Protocol, and include a Kermit server. For so-called "ASCII" (decompiled) transfers, optional special translation sequences for non-ASCII character are built-in. Kermit also handles "binary" transfers of compiled objects. Any Kermit based application ought to work with these calculators.

All 48G series have XModem built-in, and the 49 series also has a special XModem server mode. An XModem server library for the 48G series is packaged with Conn4x, designed for the 49g+, but designed to be compatible with the 48G series and 49G too. All XModem transfers are binary only, but Conn4x can do a "text" transfer by using to XModem server to tell the calculator decompile/compile objects. Conn4x optionally does translations of non-ASCII characters, and as a separate option, ASCII control codes, on the PC. Conn4x doesn't work with the 48SX and 48S, which don't have XModem built-in.

For posting source code online, I strongly recommand that you use a Kermit ASCII translation mode 3 transfer or a Conn4x "text" transfer with all translation enabed, and include the transfer header. This makes it easy for anyone to download the source code to his calculator, without editing the text or keying it in manually. It also means that everyone who uses an ASCII-based character set will see the same thing.

Physically, the "Via wire" connections on the 48 series and 49G are "3-wire" RS-232 compatible. The "Serial IR" (SIR) signal is similar to the RS-232 signal. Building an SIR to RS-232 adapter should be relatively simple, and they might be commercially available. For details of the 48 series I/O, see here. The 49G has four additional speeds easily available; multiple the 48 series speed by 1.6 to find these extra speeds. Note that the 49g+ uses USB and IrDA instead. Also note that the 49G doesn't have the hardware for IR.

The 48 series and 49g+ also have a special IR encoding ("RedEye") for sending to the printers. See here for details. HP published an INPRT program, intended for capturing IR printer output from earlier calculators. INPRT remaps some (not all) "Roman 8" characters to the modified ECMA 94 Latin No. 1 character set used on the 48 series. There are variations available that don't do the remapping. Note that INPRT on a 48 series isn't able to capture the weak IR signal from the 49g+

For a lot more information on the RPL models, see the newsgroup comp.sys.hp48, and please search the newsgroup archive before posting a question.


Edited: 7 Dec 2004, 1:34 a.m.

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