Microsoft Basic for the KIM-1 KB-6

I know KB6 existed. The ‘6’ stands for the precision in digits of the floating point number. In the documentation KB-6 is described.
Never seen a version in the wild. I know KB6 existed. The ‘6’ stands for the precision in digits of the floating point number. In the documentation KB-6 is described. Never seen a version in the wild. So the reconstruction here is not checked with the original, addresses in the reconstruction from the linker differ from the documentation.”>So the reconstruction here is not checked with the original, addresses in the reconstruction from the linker differ from the documentation.

Microsoft Basic for the KIM-1: KB9 update

More information on KB9 and a new faster and smaller version

Microsoft KB-9 Basic

Microsoft Basic for the KIM-1 (KB-9)

On this page you will find:


KB-9 stands for Microsoft Basic V1.1 for the KIM-1  with 9 digits precision. Actually, when you run it, it is called MOS Tech 6502 Basic v1.1 Copyright 1977 by Microsoft Co.
The ‘9’ stands for 9 digit precision floating point numbers. A KB-6 (6 digits precision) existed, but no copy ever turned up.

Downloads

Scanned manual
The original KIM-1 KB-9 Microsoft Basic V1.1, cassette audio wave, binary and papertape format
How to use, read this! Clear decimal, set vectors!

Resources

Articles on KB9 in the clubmagazine KIM/6502 Kenner:
– KIM Kenner 4 Siep de Vries Evaluatie 8K Basic, test of accuracy of KB-9, Dutch
– KIM Kenner 5 Uwe Schroder, English, Some Basic problems solved
– KIM Kenner 6 S. Woldringh Patches op 8K Basic Load and Save commands
– KIM Kenner 10 p 10 Microsoft Basic, Hans Otten.
– KIM Kenner 11 p 15 S. Woldringh Patches op 8K Basic part 2
– KIM Kenner 11 p 19 W. van Gelderen Read and Write on cassette for 8K Basic
(alternative commented scanned version here)
– KIM Kenner 12 p 15 Patches Microsoft Basic, Hans Otten. Trace mode Renumber
– KIM Kenner 14 p 39 Patches Microsoft Basic, Hans Otten. Calculated line numbers
– 6502 Kenner 16 p 49 Patches Microsoft Basic, W. Blonk Corrections on KIM Kenner 12
– 6502 Kenner 19 p 34 Patches Microsoft Basic, Hans Otten. Speed up Basic 10% with ROR
– 6502 Kenner 22 p 12 Patches Microsoft Basic part 1, van Nieuwenhove Koen, adapt KB-9 to Elektor Junior
– 6502 Kenner 23 p 12 Patches Microsoft Basic part 2, van Nieuwenhove Koen, adapt KB-9 to Elektor Junior
– 6502 Kenner 24 p 14 Patches Microsoft Basic part 3, van Nieuwenhove Koen, adapt KB-9 to Elektor Junior
– 6502 Kenner 25 p 6 Patches Microsoft Basic part 4, van Nieuwenhove Koen, adapt KB-9 to Elektor Junior
– 6502 Kenner 29 p 33 KB-9 Basic on Acorn SYSTEM-1
– 6502 Kenner 32 p 21 W. L. van Pelt KB-9 Basic Tokenized keywords and addresses
Language lab section in the 6502 User Notes:
– Vol 13 Basic tips, Renumber Page 1, Page 2
– Vol 14, Tips, Paging, Autiomatic Line numbers, the GET statement, USR function
Page 1, Page 2, Page 3, Page 4
– Vol 15 USR Dispatch, Load/save Basic arrays Page 1, Page 2, Page 3
-Vol 16 Line Editor Page 1, Page 2, Page 3, Page 4
-Vol 17 IEEE, Save Load cassette
Page 1, Page 2, Page 3, Page 4

Sources of KB-9 Microsoft Basic v1.1

Resources:

source in MAC format

Adapt KB-9, first step make it faster and smaller

In the previous section the pagetable article was shown, with resources to recreate from source many 6502 Basic’s, like KB-9.

Here an example how I, quick and dirty, used this to create a KB-9 named V1.2 which is smaller and faster than the original.

This is how I did it (Windows, can be done also on Linux)

  1. Download and unpack the archive of pagetable in a folder on your PC.
  2. Download and unpack the CC65 package, a C compiler, from which only the assembler and linker is used. I used the Windows binary.
  3. Copy CA65.EXE, LD65.EXE and longbranch.mac from the CC65 package to the folder where you unpacked the MS Basic source.
  4. Change whatever you like in the source. It is quite a complicated construction, with macros for every variant, so look carefully at the listing file what really is produced.
    Start with no adaptations and then go on studying the listing file and testing. The KIM-1 Simulator is a good tool for testing! Load the symbol table file to see what is where.
  5. Assemble and link with this simple batch file makekb9v2.bat, resulting in an object, a binary, a listing file and a symbol label file.
    ca65 -D kb9 msbasic.s -o tmp/kb9v2.o -l tmp/kb9v2.lst
    ld65 -C kb9.cfg tmp/kb9v2.o -o tmp/kb9v2.bin -Ln tmp/kb9v2.lbl
    
  6. Repeat step 4 and 5 until you are satisfied with the adaptations. The article listed above are a good source of inspiration.

First example: use the ROR instruction and suppress nulls sent to the terminal and Clear decimal
I changed this:

    • In define_kim.smake a comment of the following two lines:

 

; CONFIG_NULL := 1                      ; patch HO 2021
;CONFIG_ROR_WORKAROUND := 1             ; patch HO 2021
  • In init.s add this line at label COLD_START
    COLD_START:
    .ifdef SYM1
            jsr     ACCESS
    .endif
    .ifdef KBD
      .
      .
      .
    .else
      .ifndef CBM2
            cld                     ; patch for KIM-1 HO 2021
            ldx     #$FF
            stx     CURLIN+1
    

Assemble and link with the batch file makekb9v2.bat, this will deliver in the folder tmp/
– kb9v2.bin file : load as usual at $2000
– kb9v2.lbl text file
– kb9v2lst textfile

Start KB9 now at location $3F8E, label COLD_START (used to be $4065, so we gained some RAM)

Here is an archive with all files mentioned above.

And here the new KB-9 V1.2 executable, faster (no ROR instruction emulation) and a bit smaller.
You can test all this with the KIM-1 Simulator (version 0.9.3 lets you load CC65 type of symbol files)

KB-6

I know KB-6 existed. The ‘6’ stands for the precision in digits of the floating point number. In the documentation KB-6 is described.
Never seen a version in the wild. So the reconstruction here is not checked with the original, addresses in the reconstruction from the linker differ from the documentation.
Perhaps the ROR workaround or the insertion of CLD in the init.s caused this.

KB-6 it can be ‘reconstructed’ since other versions of 6 digit Microsoft Basic are in the ‘pagetable sources’.
It takes one define added in define_kim.s, changes on the original file are now:

; CONFIG_NULL := 1                      ; patch HO 2021
;CONFIG_ROR_WORKAROUND := 1             ; patch HO 2021
CONFIG_SMALL := 1                       ; patch H0 2021

Assemble and link as above. COLD_START moves to $3DF0, size shrinks to less than 8K.
Binary of KB-6 here.
As you can see in the following screenshots it works! Note the number of digits is less, as to be expected.

Microsoft Basic for the KIM-1 KB-9

Microsoft Basic for the KIM-1 KB-6, less precision, smaller program size

Microchess and MICRO_ADE sources and binaries

Microchess and MICRO-ADE are two products from Micro-Ware Limited, a company by Peter R. Jennings.

The sources of these two programs have been typed in and assembled by me from August to November 2021, and the resulting binary output is identical to my saved from cassette tape binaries.
All these files (source, binaries, papertape, audio cassette wave files, and manuals) are now
available at the KIM-1 Software page.

Robert Leedom games

In the KIM User Notes there were several KIM-1 games published by Robert Leedom.

A tiny Colossal Cave Adventure, HEXPAWN and Baseball.

With his help and others these games have been typed in again and are playable on any KIM-1 (Reproduction), PAL-1, Kim Clone, Micro-KIM.

In August 2021 I (Hans Otten) typed in the source of MICRO-Ade from the listing in the manual, the output is binary compatible with the binaries I saved from tape and are tested on the KIM-1.
The result is a source identical (in standard MOS Technology assembler format) to the listing and binary identical to the page image. I also made new high quality scan of the manual and the listing.
Micro Ade program source and binary
Scanned manual
Scanned listing

Read in the KIM KENNER archive the source of the enhancements (text by S.T. Woldringh o.a.)
The KIM club enhanced Micro Ade to version 8. Download here the binary with a 2 page command summary.
MICRO-ADE V8

Pascal-M 2k1 Pascal on the KIM-1

New version of the Pascal-M system, run Pascal programs on the KIM-1.

HEXPAWN

A game by Robert Leedom, published in 6502 user notes #13, 1979. Typed in by Dominic Bumbaco so we can play it!

Paper tape and hex dump of the program
Original article

Suppress KIM-1 echo

Original article: KIM Kenner 17 page 14, Dutch, Hans Otten. Translation 2021 Hans Otten

Problem: the KIM-1 hardware is echoing incoming serial characters to the output, no echo in software involved. Very annoying!

In the KIM Kenner 1 Siep de Vries, founder of the Dutch KIM Club mentioned how in Focal for the 6502 a trick was built in to suppress the hardware echo by manipulating the TTY out bit. From the Focal disassembly:

34B1  2C 40 17          BIT H1740
34B4  30 F9             BMI H34AF       ;=>
34B6  AD 42 17          LDA H1742
34B9  29 FE             AND #$FE
34BB  8D 42 17          STA H1742
34BE  20 5A 1E          JSR H1E5A
34C1  48                PHA
34C2  AD 42 17          LDA H1742
34C5  29 FE             AND #$FE
34C7  09 01             ORA #$01
34C9  8D 42 17          STA H1742
34CC  68                PLA
34CD  18                CLC
34CE  60                RTS

Hardware echo

I took the idea and implemented the software (wihtout knowing then in 1980 the Focal disassembly!).

The echo of incoming serial to outgoing is shown in the next figures (from the KIM user manual and the KIM Circuit poster).

The TTY KEYBD signal goes via a transistor and NAND gate U15 to PA7 port of the 6532. That signal also goes to pin 10 input  of NAND gate U26  which is the TTY out line. This is the hardware echo. When the KIM-1 sends out a character it comes  from PB0 to pin 9 of of NAND gate U26 and so comes out to the TTY Out line.
Note that PB5 is connected via an inverter to NAND gate U15. The other input is TTY IN. Making PB5 high will make the TTY input PA7 deaf.
Note PB5 is also Audio out.

Suppress echo in software


The solution to suppress the echo is making output PB0 low. The NAND gate out will now stay high, ignoring any changes on the other input, which is the incoming serial character.
Only when receiving a character PBO should be made high. Also any incoming character will now not be echoed unless the program wants to receive a character!

Example program

In this routine the standard KIM-1 GETCH routine at $1E5A is encapsulated in a subroutine that prevents the echo by setting PB0. Note that this is not a complete block of the echo, it is only active when the program calls the blocking EGETCHAR. When the program sends out charactersto a dispaly, anything typed at the keyboard will also appear at the display.
The calling program is now responsible for the echoing!

0001   1000             echo .org $1000
0002   1000             ;
0003   1000             echoflag = $17E2 ; flag: 0 normal echo
0004   1000             SBD = $1742 ; KIM 6532 PIA B data register
0005   1000             GETCH = $1E5A ; KIM TTY Getch routine 
0006   1000             ;
0007   1000 AD E2 17    EGETCHAR LDA echoflag ; if notechoflag 
0008   1003 F0 08         beq normal ;  then normal echo 
0009   1005 AD 42 17      LDA SBD  ; else set TTY bit PB0 to 0 
0010   1008 29 FE         AND #$FE  
0011   100A 8D 42 17      STA SBD ; 
0012   100D 20 5A 1E    normal JSR GETCH ; get character from input
0013   1010 48            PHA ; save
0014   1011 AD 42 17      LDA SBD ; set TTY bit PB0 
0015   1014 09 01         ORA #$01 
0016   1016 8D 42 17      STA SBD 
0017   1019 68            PLA ; restore received character
0018   101A 60            RTS 
0019   101B               .end
0020   101B               tasm: Number of errors = 0

Does EGETCHAR work on the KIM-1 clones?

Micro-KIM and PAL-1: yes, the hardware is identical, IC numbers are different
Corsham Technology: yes, though the hardware for audio is not there, there is still a NAND gate IC17C coupling PA7 and PB0.

Enhanced solution: always deaf for input
If you study the hardware shown above you see PB5 also blocks the echo. The following routine tries to use this to make the input permanent deaf.

0001   1000             echo .org $1000
0002   1000             ;
0003   1000             echoflag = $17E2 ; flag: 0 normal echo
0004   1000             SBD = $1742 ; KIM 6532 PIA B data register
0005   1000             GETCH = $1E5A ; KIM TTY Getch routine 
0006   1000             ;
0007   1000             ; no echo when reading character
0008   1000             ; 
0009   1000 AD E2 17    EGETCHAR LDA echoflag ; if not echoflag 
0010   1003 F0 08         beq normal ;  then normal echo 
0011   1005 AD 42 17      LDA SBD  ; else set TTY bit PB0 to 
0012   1008 29 FE         AND #$FE 
0013   100A 8D 42 17      STA SBD ; 
0014   100D 20 5A 1E    normal JSR GETCH ; get character form input
0015   1010 48            PHA ; save
0016   1011 AD 42 17      LDA SBD ; set TTY bit PB0 
0017   1014 09 01         ORA #$01 
0018   1016 8D 42 17      STA SBD 
0019   1019 68            PLA ; restore received character
0020   101A 60            RTS 
0021   101B             ;
0022   101B             ; no echo only at wish if reading character
0023   101B             ; note that using tape I/O will leave PB5 low
0024   101B             ; 
0025   101B AD E2 17    DGETCHAR LDA echoflag ; if notechoflag 
0026   101E F0 05         beq dnormal ;  then normal echo 
0027   1020 AD 42 17      LDA SBD  ; else set TTY bit PB0 to 
0028   1023 29 FE         AND #$FE ; PB0 low
0029   1025 29 DF       dnormal AND #$DF ; PB5 low
0030   1027 8D 42 17      STA SBD ; 
0031   102A 20 5A 1E      JSR GETCH ; get character from input
0032   102D 48            PHA ; save
0033   102E AD 42 17      LDA SBD ; set TTY bit PB0 and PB5
0034   1031 09 21         ORA #$21 ; high
0035   1033 8D 42 17      STA SBD 
0036   1036 68            PLA ; restore received character
0037   1037 60            RTS 
0038   1038               .end
0039   1038               
0040   1038               tasm: Number of errors = 0

Note that using tape I/O will leave PB5 low, allowing echo, only set high when the program calls DGETCHAR.

Does DGETCHAR work on the KIM-1 clones?

Micro-KIM and PAL-1: yes, the hardware is identical, IC numbers are different
Corsham Technology: no, PB5 is not used.