ENTCOM.TXT
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Processor Technology  ENT-to-COM File Converter  by Emmanuel ROCHE

Ok. A few weeks ago, I published on the comp.os.cpm  Newsgroup a
specification of the ENT files used on the SOL computer  to load
binary programs into memory.  As explained  then, ENT  files are
merely a dump of memory, without any checksum. As a result, they
are a very, very bad way of storing and loading a program... But
they seem to be a "de facto" standard, and several ENT files are
available  on  the Internet,  some of  which seeming  to contain
copies of lost programs... For example,  during my  quick browse
for  samples,  I noticed  a FOCAL  and a  "6.5K Byte  Shop BASIC
Revision 'C'" interpreter...  I had never heard about this BASIC
(also containing the string "MSA BASIC") before (is  anybody out
there who was a fan of the SOL computer who  could tell  us more
about it?), however, I had already saved from oblivion 2  others
FOCAL interpreters, so I decided to have a try saving it/them.

As usual, life interfered with my will. Finally, last night  the
opportunity arised: it rained all day  long, I  worked hard  all
day long,  I had  nothing to  read before  going to  bed, and  I
wanted to not think about all the work that I  had still  to do:
Programming,  with  its need  of mental  concentration, was  the
perfect solution to forget  everything during  a few  hours. (In
fact, since I had already started  playing with  the problem,  I
quickly (one hour) came to a solution.)

So, you are going to see one way to solve the problem.

However,  for  once, I  must warn  you that  I only  tested this
program on 2 ENT files... and only interactively on screen!

So, if you ever find a bug in the working of the program, please
"respond to the newsgroup", so that people can update it.

Since you will probably not be interested in  long dumps  (which
will be essentials when recreating the source  codes), I  edited
the output  of the  program, keeping  only the  most interesting
parts.

run

ENT-to-COM> Enter ENT File Name: ? focal

0000| CD A7 13 C3 B8 04 00 00 C6 00 5F 7A CE 00 57 79 |.........._z..Wy
0010| CE 00 C3 A2 17 D6 00 7D DE 00 6F 7C DE 00 67 7B |.......}..o|..g{
0020| DE 00 5F 3E 00 C9 C6 00 6F 7C CE 00 67 7B CE 00 |.._>....o|..g{..
0030| 5F 3E 00 C3 0E 18 00 00 00 00 00 00 00 00 00 00 |_>..............

Obviously  not  a  CP/M  COMmand    uses directly  the 8080
restart points.

1510| 47 CD 72 14 06 0A CD 72 14 AF D3 FA C1 E1 C9 52 |G.r....r.......R
1520| 65 77 69 6E 64 20 74 61 70 65 20 75 6E 69 74 20 |ewind tape unit
1530| 00 20 28 48 69 74 20 72 65 74 75 72 6E 20 77 68 |. (Hit return wh
1540| 65 6E 20 72 65 77 6F 75 6E 64 29 20 00 00 00 00 |en rewound) ....

A cassette tape player!  This FOCAL  must definitively  not have
run under CP/M...

1C10| 20 20 20 20 20 20 20 20 43 61 73 73 65 74 74 65 |        Cassette
1C20| 20 46 4F 43 41 4C 28 54 4D 29 20 31 2E 30 20 20 | FOCAL(TM) 1.0  
1C30| 20 28 4D 4F 44 20 30 30 30 29 0D 20 20 20 43 6F | (MOD 000).   Co
1C40| 70 79 72 69 67 68 74 20 28 43 29 20 31 39 37 38 |pyright (C) 1978
1C50| 20 50 72 6F 63 65 73 73 6F 72 20 54 65 63 68 6E | Processor Techn
1C60| 6F 6C 6F 67 79 20 43 6F 72 70 2E 0D 20 20 20 20 |ology Corp..    
1C70| 20 20 20 20 20 20 20 20 2A 2A 20 41 4C 4C 20 52 |        ** ALL R
1C80| 49 47 48 54 53 20 52 45 53 45 52 56 45 44 20 2A |IGHTS RESERVED *
1C90| 2A 0D 00 |*..

First address: 0000
Last  address: 1C92
Bytes    read: 1C93
Records  read: 39

So,  this  "Cassette FOCAL  Version 1.0"  was made  by Processor
Technology Corp. in 1978. Could someone tell us (1) if the paper
doc  is  available, and  (2) if  the source  code is  available?
(Else, it is only 7.5K, so could be  an interesting  programming
project:  FOCAL  interpreters  are  much more  rarer than  BASIC
interpreters... By the way, let us  have a  look to  the unknown
BASIC.)

Ok
run

ENT-to-COM> Enter ENT File Name: ? msabasic

0100| AF D3 FE D3 C8 CD D5 C0 CD F9 C2 C3 1A 01 21 1A |..............!.
0110| 01 22 0C 01 21 0C 02 CD 00 02 21 80 01 11 00 C9 |."..!.....!.....
0120| 01 B0 01 31 E9 CB AF 32 07 C8 7E 12 7C B8 C2 36 |...1...2..~.|..6
0130| 01 7D B9 CA 00 C9 23 13 C3 2A 01 11 00 02 01 00 |.}....#..*......
0140| A0 AF 12 7A B8 C2 4B 01 C3 60 01 13 C3 41 01 20 |...z..K..`...A.
0150| FF 22 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |."

1D10| 03 CD B1 03 21 F7 02 22 02 00 E9 57 41 4E 54 20 |....!.."...WANT
1D20| 53 49 4E 2D 43 4F 53 2D 54 41 4E 2D 41 54 4E 00 |SIN-COS-TAN-ATN.
1D30| 0D 0A 0A 0A 43 4F 52 45 20 41 4C 4C 4F 43 41 54 |....CORE ALLOCAT
1D40| 49 4F 4E 00 0D 4C 49 4E 45 20 4C 45 4E 47 54 48 |ION..LINE LENGTH
1D50| 00 0D 54 52 49 47 4F 4E 4F 4D 45 54 52 49 43 20 |..TRIGONOMETRIC
1D60| 46 55 4E 43 54 49 4F 4E 53 00 20 42 59 54 45 53 |FUNCTIONS. BYTES
1D70| 20 4F 46 20 43 4F 52 45 20 41 56 41 49 4C 41 42 | OF CORE AVAILAB
1D80| 4C 45 0A 0A 0A 00 20 20 20 20 42 59 54 45 20 53 |LE....    BYTE S
1D90| 48 4F 50 20 42 41 53 49 43 0D 0A 20 20 20 20 20 |HOP BASIC..
1DA0| 20 36 2E 35 2D 4B 20 56 45 52 53 49 4F 4E 0D 0A | 6.5-K VERSION..
1DB0| 20 20 20 20 20 20 52 45 56 49 53 49 4F 4E 20 27 |      REVISION '
1DC0| 43 27 0D 0A 0A 0A 00 0A 00 00 00 00 00 00 00 00 |C'..............

It probably starts by asking if the user wants to  keep the  sin
and trig functions, the size of memory used,  and the  length of
the command line. This is quite similar to the boot  sequence of
"Altair 8K BASIC".

2010| 2A 2A 2A 2A 2A 2A 2A 2A 2A 2A 2A 2A 2A 0D 0A 20 |*************..
2020| 20 20 20 20 20 20 20 20 20 20 20 20 20 2A 20 4D |             * M
2030| 53 41 20 42 41 53 49 43 20 2A 0D 0A 20 20 20 20 |SA BASIC *..
2040| 20 20 20 20 20 20 20 20 20 20 2A 2A 2A 2A 2A 2A |          ******
2050| 2A 2A 2A 2A 2A 2A 2A 0D 0A 00 2A 2A 2A 2A 2A 2A |*******...******
2060| 2A 2A 2A 0D 0A 00 2A 2A 2A 2A 2A 2A 2A 2A 2A 2A |***...**********
2070| 2A 2A 2A 2A 2A 0D 0A 00 00 40 00 00 40 00 00 00 |*****....@..@...
2080| 0D 0A 0A 20 20 20 20 20 20 20 20 20 20 20 20 20 |...
2090| 20 53 4F 4C 4F 53 20 56 45 52 53 49 4F 4E 0D 0A | SOLOS VERSION..
20A0| 00 0A 0A 20 20 20 20 20 43 55 54 45 52 20 56 45 |...     CUTER VE
20B0| 0D 0A 0A 20 20 20 20 20 20 20 20 20 20 20 20 20 |...
20C0| 20 43 55 54 45 52 20 56 45 52 53 49 4F 4E 0D 0A | CUTER VERSION..
20D0| 00 FF FF FF BF BF FF FF 00 40 00 10 00 40 00 00 |.........@...@..
20E0| FF FF FF FF FF FF F7 FF 00 00 00 00 00 40 00 00 |.............@..
20F0| BF FF FF FF 7F 7F FF FF 00 40 00 00 00 80 00 00 |.........@......
2100| 20 20 20 20 20 36 2E 35 20 4B 20 42 59 54 45 20 |     6.5 K BYTE
2110| 42 41 53 49 43 20 49 4E 54 45 52 50 52 45 54 45 |BASIC INTERPRETE
2120| 52 0D 0A 20 20 20 20 20 52 45 56 49 53 49 4F 4E |R..     REVISION
2130| 20 4C 45 56 45 4C 20 0D 0A 0D 0D 0A 0A 20 20 20 | LEVEL ......
2140| 20 20 20 20 20 20 20 20 43 4F 50 59 52 49 47 48 |        COPYRIGH
2150| 54 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |T ..............

First address: 0100
Last  address: 22FF
Bytes    read: 2200
Records  read: 44

What is the purpose of a Copyright notice, if there  is no  name
given? Could it be a copy of a  pirated program?  Again, let  us
hope  that  a  SOL  computer fan  will be  able to  provide some
answers (availability of paper doc, and of source code).

Finally, after those questions, at least one answer: the program
that will enable you to transform those ENT files into  CP/M BIN
files (if starting at 0000H) or  COMmand files  (if starting  at
0100H). (Let us hope that the  SOL computer  used COMmand  files
compatibles with CP/M...) (Else, change the program to  generate
only BIN (or "SOL") files.)

Ok
list
10 REM ENTCOM.BAS  by Emmanuel ROCHE
20 :
30 PRINT
40 INPUT "ENT-to-COM> Enter ENT File Name: " ; file$
50 PRINT
60 file1$ = file$ + ".ENT"
70 OPEN "I", #1, file1$
80 INPUT #1, line$
90 IF LEFT$ (line$, 2) <> "EN" THEN PRINT CHR$ (7) "First line
    must contain EN(TER), then a space, followed by the load
    address." : PRINT : PRINT line$ : PRINT : END
100 IF LEFT$ (line$, 3) = "EN " THEN sa = 4
110 IF LEFT$ (line$, 6) = "ENTER " THEN sa = 7
120 ta$ = MID$ (line$, sa)
130 ta = VAL ("&H" + ta$)
140 IF ta = 0 THEN typ$ = ".BIN"
150 IF ta = &H100 THEN typ$ = ".COM"
160 file2$ = file$ + typ$
170 OPEN "R", #2, file2$, 1
180 FIELD #2, 1 AS db2$
190 lc = 1
200 en = 1
210 :
220 INPUT #1, line$
230 la$ = LEFT$ (line$, 4)
240 PRINT la$ "|" ;
250 la = VAL ("&H" + la$)
260 IF en = 1 AND la <> ta THEN PRINT : PRINT : PRINT CHR$ (7)
    "Big problem: ENTER address <> DUMP address..." : PRINT : END
270 IF en = 1 THEN fa = la
280 IF MID$ (line$, 5, 2) = ": " THEN ra = 6
290 IF MID$ (line$, 5, 3) = ":  " THEN ra = 7
300 alpha$ = ""
310 FOR i = 0 TO 15
320     db$ = MID$ (line$, ra+i*3, 3)
330     IF db$ = "/" THEN PRINT " |" alpha$ : GOTO 510
340     PRINT db$ ;
350     db = VAL ("&H" + db$)
360     al$ = CHR$ (db)
370     LSET db2$ = al$
380     PUT #2
390     IF (db < &H20) OR (db > &H7E) THEN al$ = "."
400     alpha$ = alpha$ + al$
410     la = la + 1
420 NEXT i
430 PRINT " |" alpha$
440 lc = lc + 1
450 en = en + 1
460 ' IF lc = 24 THEN lc = 0 : WHILE INKEY$ = "" : WEND
470 IF i = 16 AND RIGHT$ (line$, 1) = "/" THEN GOTO 510
480 IF EOF (1) THEN GOTO 510
490 GOTO 220
500 :
510 PRINT
520 PRINT "First address: " ; HEX$ (fa, 4)
530 PRINT "Last  address: " ; HEX$ (la - 1, 4)
540 PRINT "Bytes    read: " ; HEX$ (la - fa, 4)
550 PRINT "Records  read: " ; HEX$ ( (la - fa) / 128, 2)
560 PRINT
570 CLOSE
580 END

system

A>That's all, folks!

Yours Sincerely,
"French Luser"

EOF