You are bidding on a used HP 48SX Scientific Calculator in mint condition.
The item has no scratches or other damage and was rarely used.
My name is engraved on the back. All manuals are included.
- CPU clock frequency: 2 MHz
- Memory clock frequency: 2 MHz
- CPU codename: Clarke
- Communication Protocol(s): Serial Transfers: Kermit (protocol); Infrared Transfers: proprietary
- On-board ROM: 256 KB
- On-board RAM: 32 KB
- Maximum additional memory per expansion card: 128 KB (SX only)
The HP-48 is a series of graphing calculators using Reverse Polish notation (RPN) and the RPL programming language, produced by Hewlett-Packard (HP) from 1990 until 2003. The series include the HP-48S, HP-48SX, HP-48G, HP-48GX, and HP-48G+, the G models being expanded and improved versions of the S models. The models with an X suffix are expandable via special RAM (memory expansion) and ROM (software application) cards. In particular, the GX models have more onboard memory than the G models. The G+ models have more onboard memory only. The SX and S models have the same amount of onboard memory.
The HP-48 series' Saturn microprocessor is a hybrid 64-bit/20-bit CPU hardware-wise but acts like a 4-bit processor in that it present nibble-based data to programs and uses a nibble-based addressing system. The main registers A, B, C, D, along with temp registers R0, R1, R2, R3, and R4 are a full 64-bits wide, but the data registers D0 & D1 are only 20-bit. External logical data fetches are transparently converted to 8-bit physical fetches. The processor has a 20-bit address bus available to code but due to the presence of the high/low nibble selection bit, only 19 bits are available externally.
Programming
The HP-48 series of calculators support a stack-based programming language named Reverse Polish Lisp (RPL), a combination of Reverse Polish Notation (RPN) and Lisp. RPL adds the concepts of lists and functions to stack-based programming, allowing the programmer to pass unevaluated code as arguments to functions, or return unevaluated code from a function by leaving it on the stack. In spite of the name, RPL resembles Forth more closely than Lisp.
