The FORTH/Assembler ROM
for the HP-71B

New: revision B

 

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HP-71B FORTH/Assembler ROM presentation

The FORTH/Assembler ROM is 48KB ROM extension of the HP-71B. It provides a FORTH implementation dedicated to the HP-71B specificities and, maybe more interesting, a resident assembler to develop LEX and BIN files on the HP-71B itself.

FORTH/Assembler ROM Documentation and Literature

• HP-71B FORTH/Assembler ROM Owner Manual , HP, April 1984
• Plug-In Module Adds FORTH Language and Assembler to a Handheld Computer in HP Journal July 1984 p37, by R. M. Miller
•  

 

FORTH/Assembler LEX Source Files (FORTH/Assembler Pac rev.A)

• FORTHROM 1A source files (from the FORTH IMS document)
• EDLEX Ver.A source files (based on the HP-71B IDS Vol.1 document)

 

 

 

The FORTH/Assembler Pac Revision B - Dec. 2020

 

This revision provides updated versions of the soft-configured 16K ROM and hard-configured 32K ROM for use in emulators.

Although the soft-configured part can be installed alone in a physical HP-71B, it has little interest without the hard-configured part.

The hard-configured part can only be used with software emulators and in ROM emulators.

 

 

Soft-configured ROM part

 

Content:

FORTH1B    LEX    3460 12/19/20 17:46            Updated version 1B

EDTEXT     BASIC  6790 02/23/84 12:00            Unchanged

EDKEYS     KEY      54 02/23/84 12:00            Unchanged

EDLEX      LEX    2384 02/23/84 12:00            Shrink version w/o SCROLL/MSG$

DBGLEX     LEX     141 02/23/84 12:00            Unchanged

KEYBOARD   LEX    1401 06/25/86 14:44            Updated to version C

STRUTIL    LEX    1856 05/05/86 18:18            Combined STRINGLX & CUSTUTIL LEX

 

The FORTH1B LEX corrects the problem of HP-71B crash if the hard-configured part of the FORTH/Assembler is missing.

Now, a "XWORD Not Found" error is generated when executing FORTH or FORTHX without the hard-configured part installed.

 

The STRUTIL LEX provides the following utility keywords (part of the User Library 1):

52/01 KEYWAIT$

52/02 SCROLL

52/03 MSG$(#)

52/04 INLINE

52/05 KEYNAM$(#)

52/06 KEYNUM($)

52/07 STD$(#)

52/08 LTRIM$($,?$)

52/09 RTRIM$($,?$)

52/0A TRIM$($,?$)

52/0B RPT$($,#)

52/0C REV$($)

52/0D LWRC$($)

52/0E LWC$($)

52/0F ROT$($,#)

52/10 SPAN($,$,?#)

52/11 MEMBER($,$,?#)

52/12 SBIT$($,#,?#,?#)

52/13 SBIT($,#,#)

 

Only the two keywords SCROLL and MSG$ were previously provided by EDLEX in the FORTH Pac A.

 

 

Hard-configured part

 

The hard-configured part includes the corrections of the two main bugs of the assembler:

the B=B+B A opcode now has the correct opcode class,

the D1=AS opcode is now correctly assembled.

 

 

Version B - Dec. 2020:

 

• FORTH/Assembler Pac Revision B Distribution Pack binary image files ready for Emu71
• FORTH LEX 1B Source Files
• EDLEX Source File w/o SCROLL/MSG$ keywords (these keywords are now provided by the STRUTIL LEX)
• FORTH Assembler Fix in the hard-configured part

 

 

Please contact me if you have any suggestions, bug fixes or enhancements to propose!

Tools:

If you want to modify and re-assemble the FORTH LEXs, you may need the following tools:
(these are 16-bit DOS applications, use DOSBox on 64-bit systems)

• SASM/SLOAD HP Tools for HP-71B code assembly (zip file)
• My "aLIFhdr" tool see doc included (zip file)

You can also refer to this updated Entry Point List:

• HP-71B Entry Points (pdf)
• HP-71B Entry Points (text source file)
  Some entries that weren't described as supported in the I.D.S. document for the HP-71B 1BBBB are now included. I recovered and formatted this list from the Areuh Tools and from other sources.

 

Contact

If you have more information on the FORTH/Assembler ROM history, or if you have bug reports or suggestions for improvement, please contact me:

J-F Garnier, 2020