Official HP48 FAQ
Answers to Frequently Asked Questions about the HP48. Version v4.62, 14 April 2000. Maintained by André Schoorl <aschoorl@engr.uvic.ca>

1. Introduction

• 1.1 Overview
• 1.2 This FAQ in Other Formats
• 1.3 Translations of this FAQ

2. Miscellaneous Questions

• 2.1 I'm a novice, and I have some questions. Where should I start?
• 2.2 What Usenet Newsgroups are there for the HP48?
• 2.3 What are some good sites for the HP48?
• 2.4 Are there any good WWW links for HP48 stuff?
• 2.5 Is there an HP48 IRC Channel?
• 2.6 How can I search for a specific HP48 file?
• 2.7 What are good places to buy HP48's and accessories?
• 2.8 What happened to EduCalc?
• 2.9 Are there any CD-ROMs with HP48 software?
• 2.10 Where can I find HP conference videotapes?
• 2.11 Are there any HP48 Emulators?
• 2.12 How can I make a dump of my HP48 ROM?
• 2.13 Is the HP48 Allowed on SATs, AP, or ACT Tests? (U.S.)
• 2.14 What is the HP49G?
• 2.15 How does the HP48 compare with other calculators?
• 2.16 What is the Universal Font Library (UFL)?
• 2.17 What are the best alternate editors?
• 2.18 Are there any PC fonts for the HP48?
• 2.19 Is the HP48 serial number available in memory?
• 2.20 What is the format of the HP48 serial number?

3. Questions about ROM versions

• 3.1 What does the SX/GX have that the S/G doesn't?
• 3.2 What is the difference between the HP48 G/GX and the HP48 S/SX?
• 3.3 What is the HP48 G+?
• 3.4 How can I tell what ROM revision I have?
• 3.5 What bugs exist in the various versions of the HP48?
• 3.6 What is new with the revision "J" ROM? (S/SX)
• 3.7 What happened to ROM revisions G, H, I, O, and Q?
• 3.8 Can I upgrade my HP48 S/SX?
• 3.9 Can I upgrade my buggy GX to the latest ROM revision?
• 3.10 What's the latest ROM version?
• 3.11 Why would I buy a S/SX rather than a G/GX?

4. Questions about the Operating System and Using the HP

• 4.1 How do I find the checksum of an object?
• 4.2 I typed RULES on my G/GX and got a crossword puzzle!
• 4.3 Why does my HP48 occasionally "freeze" for a moment?
• 4.4 What do I do if my HP48 locks up?
• 4.5 My HP48 seems to take longer to turn on and off.
• 4.6 What are all the different ON-KEY combinations?
• 4.7 What are the different interactive self-tests?
• 4.8 Why do I get an ESD error when I check my batteries with the self test?
• 4.9 I can't account for some of the RAM in the HP48!
• 4.10 What are the best methods for installing and removing libraries?
• 4.11 How can I attach large libraries?
• 4.12 What are those little numbers near the top of my screen?
• 4.13 Can I use my HP48 as a remote control?
• 4.14 Can the HP48 be used as a DTMF phone dialer?
• 4.15 How can I run a program on warmstarts and/or power-up?
• 4.16 I could speed up my HP-28S. How can I speed up my HP48?
• 4.17 What is the hidden directory and how do I access it?
• 4.18 How can I recall one object from a memory archive?
• 4.19 Are there any key combinations that aren't in the manual?
• 4.20 How do I find out about commands not in the GX manual?
• 4.21 How can one delete (or purge) an entire directory?
• 4.22 How does binary wordsize affect my calculations?
• 4.23 Can I add my own equations to HP's Equation Library?

5. Questions about Math, Plotting, and Equations

• 5.1 Why does (1/3)*3 equal 0.999999999999?
• 5.2 Why does my HP say that 0 to the power of 0 equals 1?
• 5.3 What is RPN?
• 5.4 Why did HP use RPN in their calculators?
• 5.5 Is there an alternative to calculating in RPN?
• 5.6 Why do I get unexpected values when I add temperatures?
• 5.7 How can I add my own units? What's the 1_? unit for?
• 5.8 I want `pi' to be a numeric value, not a symbol.
• 5.9 What tricks are there for manipulating matrices?
• 5.10 Can I make my HP graph any faster?
• 5.11 How do I plot inequalities?
• 5.12 How do I take the logarithm of a base other than 10 or e?
• 5.13 How do I solve quadratic equations?
• 5.14 Why do I get a complex answers for roots of negative numbers?
• 5.15 Why doesn't '(-8)^(2/3)' give me the right answer (4)?
• 5.16 How do I solve polynomials?
• 5.17 How can I do statistics for grouped data?
• 5.18 How do I generate a function table?

6. Questions about cards, data transfers, batteries, and hardware

• 6.1 My HP48 seems to making a high pitched noise.
• 6.2 Can I upgrade my S or G to more than 32K ram?
• 6.3 Can I add a lithium battery backup?
• 6.4 How can I get/build a cable for my HP48?
• 6.5 HP seems to offer two link kits with different prices.
• 6.6 Is there any communications software available?
• 6.7 Why doesn't the I/R port work farther than a few inches?
• 6.8 Can my HP48 talk to my HP100LX via Infrared?
• 6.9 Can I use my HP48 to communicate with IrDA devices?
• 6.10 Can I print to a LaserJet printer with an HP48?
• 6.11 I downloaded a program but all I get is "HPHP48-..."!
• 6.12 What is the structure of HP48 ASCII headers?
• 6.13 Why do Kermit transfers seem to get slower?
• 6.14 Why does XRECV not work sometimes? (GX)
• 6.15 Additional Tips on Transfers
• 6.16 What do the funny symbols in this document mean?
• 6.17 What are the pinouts for the HP48 serial connector?
• 6.18 Is there any information on interfacing to the HP48?
• 6.19 How can I transfer programs/data from my HP-28S to my HP48?
• 6.20 Can I use rechargeable batteries with the HP48?
• 6.21 How can I tell, from within a program, if the battery is low?
• 6.22 I lost the information on my RAM Card when I changed the battery!
• 6.23 Why do I get an "Invalid card data" error when I merge a RAM card?
• 6.24 I've heard about other manufacturer's RAM cards. Will they work?
• 6.25 How does RAM card locking work?
• 6.26 What are the advantages and disadvantages of covered ports? (GX)
• 6.27 Why does the HP48 display flicker slightly?
• 6.28 I broke the LCD screen - is there an easy way to get another?
• 6.29 How can I protect my LCD?
• 6.30 Is there a rigid (protective) case for the HP48?
• 6.31 Can I use my Amateur Radio with my HP48?

7. Questions about programs

• 7.1 Where can I get programs and information for the HP48?
• 7.2 What are the Goodies Disks and where do I get them?
• 7.3 How do I get access to the HP Calculator BBS?
• 7.4 What are files that end with ".zip", ".Z", ".gz", or ".bz2"?
• 7.5 What is a "ship" file?
• 7.6 What is the ASC format and how can I use it?
• 7.7 What is the HYDE library, and how do I get rid of it?
• 7.8 What is the Minehunt game, and how do I use it?

8. Questions about programming and advanced user functions

• 8.1 I've heard the names RPL, Saturn, STAR, GL etc... What are they?
• 8.2 Is there a C compiler for the HP48?
• 8.3 Why do SysRPL programs run faster than UserRPL programs?
• 8.4 What is a good reference for learning SysRPL and ML?
• 8.5 Can I make my own libraries? Can I split others?
• 8.6 How do I know what library ID number to use for my program?
• 8.7 What information is there on the internals of the HP48?
• 8.8 Where can I get some programming development tools?
• 8.9 I know UserRPL. How do I get started in SysRPL?
• 8.10 Are there any viruses for the HP48?
• 8.11 How do I store fields of variable length effectively?
• 8.12 What is "Vectored Enter", and how do I use it?
• 8.13 What is "WSLOG"?
• 8.14 What are SYSEVALs?
• 8.15 What are some useful SYSEVALs?
• 8.16 What are LIBEVALs?
• 8.17 What are some useful LIBEVALs? (GX)
• 8.18 What is the format of a GROB object?
• 8.19 What is the AUR and what information does it contain?
• 8.20 What is the syntax for INFORM, CHOOSE, and MSGBOX? (GX)
• 8.21 How do I put checkfields in my INFORM menus?
• 8.22 What is the syntax for the INPUT command?

9. Appendix A: Various Useful Functions

• 9.1 ASC Functions
• 9.2 OBJFIX
• 9.3 FIXIT
• 9.4 LASTX
• 9.5 Compact Data Storage
• 9.6 HP82240B Printer Codes

10. Appendix B: GX Specific Information

• 10.1 What's new in the HP48 G/GX?
• 10.2 Examples of INFORM, CHOOSE, and MSGBOX
• 10.3 Some useful LIBEVALs

11. Appendix C: Details of Bugs

• 11.1 The EquationWriter Bug
• 11.2 Rotation Rate to Angular Frequency Conversion Bug

12. Appendix D: Hardware Additions

• 12.1 How to Make a Serial Cable
• 12.2 Using a modem with the HP48
• 12.3 Additional Information on the HP48 and RS-232
• 12.4 Using Non-HP RAM Cards
• 12.5 Where can one obtain third party RAM cards?

13. Appendix E: Where to get HP48 Programs

• 13.1 Best Programs and Where to Get Them List
• 13.2 Other Web / FTP Sites
• 13.3 FTP by Electronic Mail
• 13.4 Bulletin Boards with HP48 Programs
• 13.5 HP Goodies Disks

14. Contributors