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F/M\cTut1
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
| Tape/disk: | Home » Personal collection » Acorn ADFS disks » Electron_User_Group » EUG_24.ADF |
| Filename: | F/M\cTut1 |
| Read OK: | ✔ |
| File size: | 18DF bytes |
| Load address: | 6D204556 |
| Exec address: | 7574632F |
File contents
USING THE ASSEMBLER 7
~~~~~~~~~~~~~~~~~~~~~
By Richard Dimond
I hope that my last contribution was reasonably understandable and not too
overwhelming!! Like most of my programs, it just grew and grew!! I have
a program that grew too big for 32k and hope to shorten it by M/coding it.
Having said that, before I describe the promised adventure program, I want
to comment on two routines which were used in the programs given last time
as these will be often used in M/code.
In the Miner program, when you move around, the play area is re-drawn each
time from the data starting at a different address. This address is
calculated by adding or subtracting an amount depending on which way you
move.
For addition, the carry flag must be cleared first then the low byte
values added followed by the high byte values. Thus -
CLC:LDAaddr:ADC#xlow:STAaddr
LDAaddr+1:ADC#xhigh:STAaddr
adds the two byte value 'x' to the address held at 'addr' and stores it at
this address.
For subtraction, the routine is the same except the carry flag must be set
first.
In the MINsrc1 program line 650, the value to be added is first stored in
&90. This is then added after loading the value from 'data' and stored
again. As there is no high byte value to add, the ADC#0 in the line adds
1 to the high byte if the carry flag is set by the addition of the low
byte. Lines 660 and 670 are similar for changing the address held in
'addr'.
The other routine is for transferring blocks of data from one memory area
to another. This is done with a loop similar to those I have already
given. In line 680 of the program referred to, data from the address in
&80 is loaded into A register and stored into the address in'addr' with
the commands - LDA(&80),Y:STA(addr),Y. As Y register is loaded with 17 at
the start, this is added to the addresses and each time round the loop Y
is decreased until the value goes negative when the value in Y falls below
zero. In this way 18 bytes are transferred.
Another loop often used is this -
LDY#0
.loop
<transfer commands>
INY:BNEloop
RTS
This transfers 256 bytes, ie a page of data and can be extended to
transfer several pages by increasing the high bytes of the addresses each
time the loop is completed and either counting the number of pages using X
register as a counter or comparing the high byte of one of the addresses.
Now for the game such as it is!! It was based on a series of articles in
'Let's Compute' - remember the kid's magazine? It is far from complete as
the series was unfinished when the magazine stopped publication. It was
also written in rather peculiar Basic as it was to be adapted for other
machines and I thoght it a challenge to rewrite in M/code. I thoght also
that there was sufficient to give you some ideas on writing an adventure
program in M/code and also to show some further routines. If anyone has
ideas on how to complete the game or to write another, I would be glad to
help.
First I will give a breakdown of the program referring to the lines of the
assembler which produce the code as I did last time.
Lines 120 - 1090 are the subroutines
2000 - 2240 are the main loop
5000 - the buffer for osword (&FFF1) for the input.
5010 - title data
5020 - 5030 data for printing the directions
5040 - 5240 message data
5250 - 5280 table of message addresses
5290 - flag for the messages
5300 - 5550 words for COMMANDS
5310 directions - single letters
5320 directions - words
5340 actions
5400 useful objects to take
5470 other objects
5550 inventory
5570 - stores the current lacation number
5580 - 5780 locations
5790 - 5820 table of location addresses
5830 - 6030 movement data
6040 - 6180 object descriptions
6190 - 6210 table of addresses for these
6220 - data for object positions
6230 - data for objects held
6240 - two bytes for holding the action numbers
I will describe the working of the program from the start (line 2000) and
explain the subroutines as they are used again referring to the lines in
the assembler listing.
At the start you are in location 1 - The Control Room as the value in
'loc' (line 5570) is 1.
Line 2010 selects MODE 6 followed by two OSNEWLs.
2020 uses routine 'rep' to print 12 spaces <TAB(12)>, and prints the
title using routine 'prt' and an OSNEWL.
2030 prints the underline
The main loop starts at line 2040.
The messages are printed by loading A register with the number of the
message and then calling the routine 'prtmess'. The value in A is doubled
by ASL A, 2 subtracted and the value transferred to Y register. Thus Y is
loaded with 0, 2, 4,... according to which message is to be printed. This
is then used as an index to the two bytes or the address of the message.
These two values are then loaded into X and Y registers before calling the
routine 'prt'.
The routine 'prtloc' works in the same way except that A register is
loaded with the value of the current location held in 'loc' so that you
are told where you are.
This method of referring to an address in a table is often used in M/code.
In this program it is used to set up the printing of the data and what you
can do according to the location you are since the value in 'loc' is used
for the index.
Line 2080 prints message 2 and the routine 'ldobs' is called. This
routine searches the data 'obsdat' (line 6220) - note that each four bytes
are in reverse order as they are entered using EQUD.
The data is compared with the location number and, if they are equal, the
object number, which is the value in Y register, is printed with the
routine 'prtob' (line 440). The 'obflag' (&75) is set to -1 (&FF) to show
that an object has be found.
On completion of the search, the program jumps to 'ret' and the obflag is
compared with &FF. If this is equal the routine ends. If no object is
found then the obflag is zero and message 15 is printed (line 580).
00000000 0d 55 53 49 4e 47 20 54 48 45 20 41 53 53 45 4d |.USING THE ASSEM| 00000010 42 4c 45 52 20 37 0d 7e 7e 7e 7e 7e 7e 7e 7e 7e |BLER 7.~~~~~~~~~| 00000020 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e 7e 0d 42 79 20 |~~~~~~~~~~~~.By | 00000030 52 69 63 68 61 72 64 20 44 69 6d 6f 6e 64 0d 0d |Richard Dimond..| 00000040 49 20 68 6f 70 65 20 74 68 61 74 20 6d 79 20 6c |I hope that my l| 00000050 61 73 74 20 63 6f 6e 74 72 69 62 75 74 69 6f 6e |ast contribution| 00000060 20 77 61 73 20 72 65 61 73 6f 6e 61 62 6c 79 20 | was reasonably | 00000070 75 6e 64 65 72 73 74 61 6e 64 61 62 6c 65 20 61 |understandable a| 00000080 6e 64 20 6e 6f 74 20 74 6f 6f 0d 6f 76 65 72 77 |nd not too.overw| 00000090 68 65 6c 6d 69 6e 67 21 21 1a 20 20 4c 69 6b 65 |helming!!. Like| 000000a0 20 6d 6f 73 74 20 6f 66 20 6d 79 20 70 72 6f 67 | most of my prog| 000000b0 72 61 6d 73 2c 20 69 74 20 6a 75 73 74 20 67 72 |rams, it just gr| 000000c0 65 77 20 61 6e 64 20 67 72 65 77 21 21 20 20 49 |ew and grew!! I| 000000d0 20 68 61 76 65 0d 61 20 70 72 6f 67 72 61 6d 20 | have.a program | 000000e0 74 68 61 74 20 67 72 65 77 20 74 6f 6f 20 62 69 |that grew too bi| 000000f0 67 20 66 6f 72 20 33 32 6b 20 61 6e 64 20 68 6f |g for 32k and ho| 00000100 70 65 20 74 6f 20 73 68 6f 72 74 65 6e 20 69 74 |pe to shorten it| 00000110 20 62 79 20 4d 2f 63 6f 64 69 6e 67 20 69 74 2e | by M/coding it.| 00000120 0d 0d 48 61 76 69 6e 67 20 73 61 69 64 20 74 68 |..Having said th| 00000130 61 74 2c 20 62 65 66 6f 72 65 20 49 20 64 65 73 |at, before I des| 00000140 63 72 69 62 65 20 74 68 65 20 70 72 6f 6d 69 73 |cribe the promis| 00000150 65 64 20 61 64 76 65 6e 74 75 72 65 20 70 72 6f |ed adventure pro| 00000160 67 72 61 6d 2c 20 49 20 77 61 6e 74 0d 74 6f 20 |gram, I want.to | 00000170 63 6f 6d 6d 65 6e 74 20 6f 6e 20 74 77 6f 20 72 |comment on two r| 00000180 6f 75 74 69 6e 65 73 20 77 68 69 63 68 20 77 65 |outines which we| 00000190 72 65 20 75 73 65 64 20 69 6e 20 74 68 65 20 70 |re used in the p| 000001a0 72 6f 67 72 61 6d 73 20 67 69 76 65 6e 20 6c 61 |rograms given la| 000001b0 73 74 20 74 69 6d 65 0d 61 73 20 74 68 65 73 65 |st time.as these| 000001c0 20 77 69 6c 6c 20 62 65 20 6f 66 74 65 6e 20 75 | will be often u| 000001d0 73 65 64 20 69 6e 20 4d 2f 63 6f 64 65 2e 0d 0d |sed in M/code...| 000001e0 49 6e 20 74 68 65 20 4d 69 6e 65 72 20 70 72 6f |In the Miner pro| 000001f0 67 72 61 6d 2c 20 77 68 65 6e 20 79 6f 75 20 6d |gram, when you m| 00000200 6f 76 65 20 61 72 6f 75 6e 64 2c 20 74 68 65 20 |ove around, the | 00000210 70 6c 61 79 20 61 72 65 61 20 69 73 20 72 65 2d |play area is re-| 00000220 64 72 61 77 6e 20 65 61 63 68 0d 74 69 6d 65 20 |drawn each.time | 00000230 66 72 6f 6d 1a 20 74 68 65 1a 20 64 61 74 61 1a |from. the. data.| 00000240 20 73 74 61 72 74 69 6e 67 1a 20 61 74 1a 20 61 | starting. at. a| 00000250 1a 20 64 69 66 66 65 72 65 6e 74 20 61 64 64 72 |. different addr| 00000260 65 73 73 2e 20 20 54 68 69 73 20 61 64 64 72 65 |ess. This addre| 00000270 73 73 20 69 73 0d 63 61 6c 63 75 6c 61 74 65 64 |ss is.calculated| 00000280 20 62 79 20 61 64 64 69 6e 67 20 6f 72 20 73 75 | by adding or su| 00000290 62 74 72 61 63 74 69 6e 67 1a 20 61 6e 1a 20 61 |btracting. an. a| 000002a0 6d 6f 75 6e 74 20 64 65 70 65 6e 64 69 6e 67 20 |mount depending | 000002b0 6f 6e 20 77 68 69 63 68 20 77 61 79 20 79 6f 75 |on which way you| 000002c0 0d 6d 6f 76 65 2e 20 20 0d 0d 46 6f 72 1a 20 61 |.move. ..For. a| 000002d0 64 64 69 74 69 6f 6e 2c 1a 20 74 68 65 1a 20 63 |ddition,. the. c| 000002e0 61 72 72 79 1a 20 66 6c 61 67 1a 20 6d 75 73 74 |arry. flag. must| 000002f0 1a 20 62 65 20 63 6c 65 61 72 65 64 20 66 69 72 |. be cleared fir| 00000300 73 74 20 74 68 65 6e 20 74 68 65 20 6c 6f 77 20 |st then the low | 00000310 62 79 74 65 0d 76 61 6c 75 65 73 20 61 64 64 65 |byte.values adde| 00000320 64 20 66 6f 6c 6c 6f 77 65 64 20 62 79 20 74 68 |d followed by th| 00000330 65 20 68 69 67 68 20 62 79 74 65 20 76 61 6c 75 |e high byte valu| 00000340 65 73 2e 20 20 54 68 75 73 20 2d 0d 0d 20 20 20 |es. Thus -.. | 00000350 20 20 20 20 20 20 20 43 4c 43 3a 4c 44 41 61 64 | CLC:LDAad| 00000360 64 72 3a 41 44 43 23 78 6c 6f 77 3a 53 54 41 61 |dr:ADC#xlow:STAa| 00000370 64 64 72 0d 20 20 20 20 20 20 20 20 20 20 4c 44 |ddr. LD| 00000380 41 61 64 64 72 2b 31 3a 41 44 43 23 78 68 69 67 |Aaddr+1:ADC#xhig| 00000390 68 3a 53 54 41 61 64 64 72 0d 0d 61 64 64 73 20 |h:STAaddr..adds | 000003a0 74 68 65 20 74 77 6f 20 62 79 74 65 20 76 61 6c |the two byte val| 000003b0 75 65 20 27 78 27 20 74 6f 20 74 68 65 20 61 64 |ue 'x' to the ad| 000003c0 64 72 65 73 73 20 68 65 6c 64 20 61 74 20 27 61 |dress held at 'a| 000003d0 64 64 72 27 20 61 6e 64 20 73 74 6f 72 65 73 20 |ddr' and stores | 000003e0 69 74 20 61 74 0d 74 68 69 73 20 61 64 64 72 65 |it at.this addre| 000003f0 73 73 2e 0d 0d 46 6f 72 20 73 75 62 74 72 61 63 |ss...For subtrac| 00000400 74 69 6f 6e 2c 20 74 68 65 20 72 6f 75 74 69 6e |tion, the routin| 00000410 65 20 69 73 20 74 68 65 20 73 61 6d 65 20 65 78 |e is the same ex| 00000420 63 65 70 74 20 74 68 65 20 63 61 72 72 79 20 66 |cept the carry f| 00000430 6c 61 67 20 6d 75 73 74 20 62 65 20 73 65 74 0d |lag must be set.| 00000440 66 69 72 73 74 2e 0d 0d 49 6e 1a 20 74 68 65 20 |first...In. the | 00000450 4d 49 4e 73 72 63 31 20 70 72 6f 67 72 61 6d 20 |MINsrc1 program | 00000460 6c 69 6e 65 20 36 35 30 2c 20 74 68 65 20 76 61 |line 650, the va| 00000470 6c 75 65 20 74 6f 20 62 65 20 61 64 64 65 64 20 |lue to be added | 00000480 69 73 20 66 69 72 73 74 20 73 74 6f 72 65 64 20 |is first stored | 00000490 69 6e 0d 26 39 30 2e 20 20 54 68 69 73 1a 20 69 |in.&90. This. i| 000004a0 73 1a 20 74 68 65 6e 1a 20 61 64 64 65 64 20 61 |s. then. added a| 000004b0 66 74 65 72 20 6c 6f 61 64 69 6e 67 20 74 68 65 |fter loading the| 000004c0 20 76 61 6c 75 65 20 66 72 6f 6d 20 27 64 61 74 | value from 'dat| 000004d0 61 27 20 61 6e 64 20 73 74 6f 72 65 64 0d 61 67 |a' and stored.ag| 000004e0 61 69 6e 2e 20 20 41 73 20 74 68 65 72 65 20 69 |ain. As there i| 000004f0 73 20 6e 6f 1a 20 68 69 67 68 20 62 79 74 65 20 |s no. high byte | 00000500 76 61 6c 75 65 20 74 6f 20 61 64 64 2c 20 74 68 |value to add, th| 00000510 65 20 41 44 43 23 30 20 69 6e 20 74 68 65 20 6c |e ADC#0 in the l| 00000520 69 6e 65 20 61 64 64 73 0d 31 20 74 6f 20 74 68 |ine adds.1 to th| 00000530 65 20 68 69 67 68 20 62 79 74 65 20 69 66 1a 20 |e high byte if. | 00000540 74 68 65 1a 20 63 61 72 72 79 1a 20 66 6c 61 67 |the. carry. flag| 00000550 1a 20 69 73 20 73 65 74 20 62 79 20 74 68 65 20 |. is set by the | 00000560 61 64 64 69 74 69 6f 6e 20 6f 66 20 74 68 65 20 |addition of the | 00000570 6c 6f 77 0d 62 79 74 65 2e 1a 20 20 4c 69 6e 65 |low.byte.. Line| 00000580 73 1a 20 36 36 30 20 61 6e 64 20 36 37 30 20 61 |s. 660 and 670 a| 00000590 72 65 20 73 69 6d 69 6c 61 72 20 66 6f 72 20 63 |re similar for c| 000005a0 68 61 6e 67 69 6e 67 20 74 68 65 1a 20 61 64 64 |hanging the. add| 000005b0 72 65 73 73 1a 20 68 65 6c 64 1a 20 69 6e 0d 27 |ress. held. in.'| 000005c0 61 64 64 72 27 2e 0d 0d 54 68 65 20 6f 74 68 65 |addr'...The othe| 000005d0 72 20 72 6f 75 74 69 6e 65 20 69 73 20 66 6f 72 |r routine is for| 000005e0 20 74 72 61 6e 73 66 65 72 72 69 6e 67 20 62 6c | transferring bl| 000005f0 6f 63 6b 73 20 6f 66 20 64 61 74 61 20 66 72 6f |ocks of data fro| 00000600 6d 1a 20 6f 6e 65 20 6d 65 6d 6f 72 79 20 61 72 |m. one memory ar| 00000610 65 61 0d 74 6f 1a 20 61 6e 6f 74 68 65 72 2e 1a |ea.to. another..| 00000620 20 20 54 68 69 73 20 69 73 20 64 6f 6e 65 20 77 | This is done w| 00000630 69 74 68 20 61 20 6c 6f 6f 70 20 73 69 6d 69 6c |ith a loop simil| 00000640 61 72 20 74 6f 20 74 68 6f 73 65 1a 20 49 1a 20 |ar to those. I. | 00000650 68 61 76 65 1a 20 61 6c 72 65 61 64 79 0d 67 69 |have. already.gi| 00000660 76 65 6e 2e 20 20 49 6e 20 6c 69 6e 65 1a 20 36 |ven. In line. 6| 00000670 38 30 1a 20 6f 66 20 74 68 65 20 70 72 6f 67 72 |80. of the progr| 00000680 61 6d 20 72 65 66 65 72 72 65 64 20 74 6f 2c 20 |am referred to, | 00000690 64 61 74 61 20 66 72 6f 6d 20 74 68 65 20 61 64 |data from the ad| 000006a0 64 72 65 73 73 20 69 6e 0d 26 38 30 20 69 73 20 |dress in.&80 is | 000006b0 6c 6f 61 64 65 64 20 69 6e 74 6f 20 41 1a 20 72 |loaded into A. r| 000006c0 65 67 69 73 74 65 72 1a 20 61 6e 64 1a 20 73 74 |egister. and. st| 000006d0 6f 72 65 64 20 69 6e 74 6f 20 74 68 65 20 61 64 |ored into the ad| 000006e0 64 72 65 73 73 20 69 6e 27 61 64 64 72 27 20 77 |dress in'addr' w| 000006f0 69 74 68 0d 74 68 65 20 63 6f 6d 6d 61 6e 64 73 |ith.the commands| 00000700 20 2d 20 4c 44 41 28 26 38 30 29 2c 59 3a 53 54 | - LDA(&80),Y:ST| 00000710 41 28 61 64 64 72 29 2c 59 2e 20 20 41 73 20 59 |A(addr),Y. As Y| 00000720 20 72 65 67 69 73 74 65 72 20 69 73 20 6c 6f 61 | register is loa| 00000730 64 65 64 20 77 69 74 68 20 31 37 20 61 74 0d 74 |ded with 17 at.t| 00000740 68 65 20 73 74 61 72 74 2c 20 74 68 69 73 20 69 |he start, this i| 00000750 73 20 61 64 64 65 64 20 74 6f 20 74 68 65 20 61 |s added to the a| 00000760 64 64 72 65 73 73 65 73 1a 20 61 6e 64 1a 20 65 |ddresses. and. e| 00000770 61 63 68 20 74 69 6d 65 20 72 6f 75 6e 64 20 74 |ach time round t| 00000780 68 65 20 6c 6f 6f 70 20 59 0d 69 73 20 64 65 63 |he loop Y.is dec| 00000790 72 65 61 73 65 64 20 75 6e 74 69 6c 20 74 68 65 |reased until the| 000007a0 20 76 61 6c 75 65 20 67 6f 65 73 20 6e 65 67 61 | value goes nega| 000007b0 74 69 76 65 20 77 68 65 6e 20 74 68 65 20 76 61 |tive when the va| 000007c0 6c 75 65 20 69 6e 20 59 20 66 61 6c 6c 73 20 62 |lue in Y falls b| 000007d0 65 6c 6f 77 0d 7a 65 72 6f 2e 20 20 49 6e 20 74 |elow.zero. In t| 000007e0 68 69 73 20 77 61 79 20 31 38 20 62 79 74 65 73 |his way 18 bytes| 000007f0 20 61 72 65 20 74 72 61 6e 73 66 65 72 72 65 64 | are transferred| 00000800 2e 0d 0d 41 6e 6f 74 68 65 72 20 6c 6f 6f 70 20 |...Another loop | 00000810 6f 66 74 65 6e 20 75 73 65 64 20 69 73 20 74 68 |often used is th| 00000820 69 73 20 2d 0d 0d 20 20 20 20 20 20 20 20 20 20 |is -.. | 00000830 20 20 20 20 20 20 20 20 20 4c 44 59 23 30 0d 20 | LDY#0. | 00000840 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000850 20 20 2e 6c 6f 6f 70 0d 20 20 20 20 20 20 20 20 | .loop. | 00000860 20 20 20 20 20 20 20 20 20 20 20 3c 74 72 61 6e | <tran| 00000870 73 66 65 72 20 63 6f 6d 6d 61 6e 64 73 3e 0d 20 |sfer commands>. | 00000880 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000890 20 20 49 4e 59 3a 42 4e 45 6c 6f 6f 70 0d 20 20 | INY:BNEloop. | 000008a0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 000008b0 20 52 54 53 0d 0d 54 68 69 73 1a 20 74 72 61 6e | RTS..This. tran| 000008c0 73 66 65 72 73 1a 20 32 35 36 1a 20 62 79 74 65 |sfers. 256. byte| 000008d0 73 2c 1a 20 69 65 20 61 20 70 61 67 65 20 6f 66 |s,. ie a page of| 000008e0 20 64 61 74 61 20 61 6e 64 1a 20 63 61 6e 1a 20 | data and. can. | 000008f0 62 65 1a 20 65 78 74 65 6e 64 65 64 1a 20 74 6f |be. extended. to| 00000900 0d 74 72 61 6e 73 66 65 72 20 73 65 76 65 72 61 |.transfer severa| 00000910 6c 20 70 61 67 65 73 20 62 79 20 69 6e 63 72 65 |l pages by incre| 00000920 61 73 69 6e 67 1a 20 74 68 65 20 68 69 67 68 20 |asing. the high | 00000930 62 79 74 65 73 20 6f 66 20 74 68 65 20 61 64 64 |bytes of the add| 00000940 72 65 73 73 65 73 20 65 61 63 68 0d 74 69 6d 65 |resses each.time| 00000950 20 74 68 65 20 6c 6f 6f 70 20 69 73 20 63 6f 6d | the loop is com| 00000960 70 6c 65 74 65 64 20 61 6e 64 20 65 69 74 68 65 |pleted and eithe| 00000970 72 20 63 6f 75 6e 74 69 6e 67 20 74 68 65 20 6e |r counting the n| 00000980 75 6d 62 65 72 20 6f 66 20 70 61 67 65 73 20 75 |umber of pages u| 00000990 73 69 6e 67 20 58 0d 72 65 67 69 73 74 65 72 20 |sing X.register | 000009a0 61 73 20 61 20 63 6f 75 6e 74 65 72 20 6f 72 20 |as a counter or | 000009b0 63 6f 6d 70 61 72 69 6e 67 20 74 68 65 20 68 69 |comparing the hi| 000009c0 67 68 20 62 79 74 65 20 6f 66 20 6f 6e 65 20 6f |gh byte of one o| 000009d0 66 20 74 68 65 20 61 64 64 72 65 73 73 65 73 2e |f the addresses.| 000009e0 0d 0d 4e 6f 77 1a 20 66 6f 72 20 74 68 65 20 67 |..Now. for the g| 000009f0 61 6d 65 20 73 75 63 68 20 61 73 20 69 74 20 69 |ame such as it i| 00000a00 73 21 21 20 20 49 74 20 77 61 73 20 62 61 73 65 |s!! It was base| 00000a10 64 20 6f 6e 20 61 20 73 65 72 69 65 73 20 6f 66 |d on a series of| 00000a20 20 61 72 74 69 63 6c 65 73 20 69 6e 0d 27 4c 65 | articles in.'Le| 00000a30 74 27 73 20 43 6f 6d 70 75 74 65 27 20 2d 20 72 |t's Compute' - r| 00000a40 65 6d 65 6d 62 65 72 20 74 68 65 20 6b 69 64 27 |emember the kid'| 00000a50 73 20 6d 61 67 61 7a 69 6e 65 3f 20 20 49 74 20 |s magazine? It | 00000a60 69 73 20 66 61 72 20 66 72 6f 6d 20 63 6f 6d 70 |is far from comp| 00000a70 6c 65 74 65 20 61 73 0d 74 68 65 20 73 65 72 69 |lete as.the seri| 00000a80 65 73 20 77 61 73 20 75 6e 66 69 6e 69 73 68 65 |es was unfinishe| 00000a90 64 20 77 68 65 6e 1a 20 74 68 65 1a 20 6d 61 67 |d when. the. mag| 00000aa0 61 7a 69 6e 65 20 73 74 6f 70 70 65 64 20 70 75 |azine stopped pu| 00000ab0 62 6c 69 63 61 74 69 6f 6e 2e 20 20 49 74 20 77 |blication. It w| 00000ac0 61 73 0d 61 6c 73 6f 20 77 72 69 74 74 65 6e 20 |as.also written | 00000ad0 69 6e 20 72 61 74 68 65 72 20 70 65 63 75 6c 69 |in rather peculi| 00000ae0 61 72 20 42 61 73 69 63 20 61 73 1a 20 69 74 1a |ar Basic as. it.| 00000af0 20 77 61 73 1a 20 74 6f 20 62 65 20 61 64 61 70 | was. to be adap| 00000b00 74 65 64 20 66 6f 72 20 6f 74 68 65 72 0d 6d 61 |ted for other.ma| 00000b10 63 68 69 6e 65 73 20 61 6e 64 20 49 20 74 68 6f |chines and I tho| 00000b20 67 68 74 20 69 74 20 61 20 63 68 61 6c 6c 65 6e |ght it a challen| 00000b30 67 65 20 74 6f 20 72 65 77 72 69 74 65 20 69 6e |ge to rewrite in| 00000b40 1a 20 4d 2f 63 6f 64 65 2e 20 20 49 20 74 68 6f |. M/code. I tho| 00000b50 67 68 74 20 61 6c 73 6f 0d 74 68 61 74 20 74 68 |ght also.that th| 00000b60 65 72 65 20 77 61 73 20 73 75 66 66 69 63 69 65 |ere was sufficie| 00000b70 6e 74 20 74 6f 20 67 69 76 65 20 79 6f 75 20 73 |nt to give you s| 00000b80 6f 6d 65 20 69 64 65 61 73 20 6f 6e 20 77 72 69 |ome ideas on wri| 00000b90 74 69 6e 67 1a 20 61 6e 1a 20 61 64 76 65 6e 74 |ting. an. advent| 00000ba0 75 72 65 0d 70 72 6f 67 72 61 6d 1a 20 69 6e 1a |ure.program. in.| 00000bb0 20 4d 2f 63 6f 64 65 20 61 6e 64 20 61 6c 73 6f | M/code and also| 00000bc0 20 74 6f 20 73 68 6f 77 20 73 6f 6d 65 20 66 75 | to show some fu| 00000bd0 72 74 68 65 72 20 72 6f 75 74 69 6e 65 73 2e 20 |rther routines. | 00000be0 20 49 66 20 61 6e 79 6f 6e 65 20 68 61 73 0d 69 | If anyone has.i| 00000bf0 64 65 61 73 20 6f 6e 20 68 6f 77 1a 20 74 6f 20 |deas on how. to | 00000c00 63 6f 6d 70 6c 65 74 65 20 74 68 65 20 67 61 6d |complete the gam| 00000c10 65 20 6f 72 20 74 6f 20 77 72 69 74 65 20 61 6e |e or to write an| 00000c20 6f 74 68 65 72 2c 20 49 20 77 6f 75 6c 64 20 62 |other, I would b| 00000c30 65 20 67 6c 61 64 20 74 6f 0d 68 65 6c 70 2e 20 |e glad to.help. | 00000c40 20 0d 0d 46 69 72 73 74 20 49 20 77 69 6c 6c 20 | ..First I will | 00000c50 67 69 76 65 20 61 20 62 72 65 61 6b 64 6f 77 6e |give a breakdown| 00000c60 20 6f 66 20 74 68 65 20 70 72 6f 67 72 61 6d 20 | of the program | 00000c70 72 65 66 65 72 72 69 6e 67 20 74 6f 20 74 68 65 |referring to the| 00000c80 20 6c 69 6e 65 73 20 6f 66 20 74 68 65 0d 61 73 | lines of the.as| 00000c90 73 65 6d 62 6c 65 72 20 77 68 69 63 68 20 70 72 |sembler which pr| 00000ca0 6f 64 75 63 65 20 74 68 65 20 63 6f 64 65 20 61 |oduce the code a| 00000cb0 73 20 49 20 64 69 64 20 6c 61 73 74 20 74 69 6d |s I did last tim| 00000cc0 65 2e 0d 0d 4c 69 6e 65 73 20 31 32 30 20 2d 20 |e...Lines 120 - 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