Hard & Soft - thoughts about MODEM.

                                          
CALL ME, CALL...         
 -------------------------        
  Marat (c)1999 
                                          
 We were prompted to write this article 
different thoughts walking in our violent 
heads, thoughts tormenting us during the day and 
at night, thoughts o ... . .  .   . -=MODEM=- 
                                          
MODEM-electronic device for transmitting 
data between computers via telephone 
lines.                                    
                                    
The modems themselves were invented a long time ago and 
used on various computers 
platforms with great success.  Developing 
in parallel with computers they conquered 
their peaks became faster and faster 
smarter and by this time already have 
a huge number of possibilities (set and 
                                          
number identification (Caller ID), fax, voice 
functions, etc.) .                          
 One day the moment came when we decided: 
"Stop wasting time, it's time to get started 
own modem and work at home, rather than 
in the editorial office." Agree, it’s more pleasant to sit 
at home and, drinking tea, slide along the Web. 
We need a modem as another degree 
personal freedom.  And for comfort - so that 
calmly on a day off to get in line - 
new material and send it to the editor and 
at the same time, don’t worry about whether I’ll make it on time 
bring him. But desire alone is not enough to 
the wish has become reality and we 
began the search. Having delved into various 
literature we found out that on the platform 
ZX-SPECTRUM has more than one modem:   
 ZX-MODEM,   
 X-MODEM,   
 X-TRADE MODEM,   
 etc.   
                     
 ZX-MODEM - developed by NTK Plus.       
The modem connects directly to 
tires of your Spectrum, without using 
interface. Speed ​​600-1200 Baud.        
                   
 X-MODEM     
The modem is connected to the tape recorder port.   
Speed 600-1200 Baud.                    
                   
 X-TRADE MODEM - development of X-TRADE.      
In relation to the previous two, the most 
intelligent (number dialing, caller ID...).   
Connects to the computer bus.           
Speed 2400 Baud.                        
                   
T. j. X-TRADE automatically moves to 
different price plan, then the first ones remain 
two modems. Theyare simple in design 
and are reconfigured according to program speed 
in many ways.  We will try to tell you about them. 
go into more detail.                      
                   
                                          
              +-----------+               
              | ZX-MODEM. |.              
              +-----------+.              
               .............              
                                          
 ZX-MODEM connects without an interface. 
In addition to the hardware, it is necessary to launch 
Install the modem support program.         
ZX-MODEM-direct connection modem, i.e.  he 
connects to the telephone line. In the scheme 
modem connection with the telephone line is carried out 
is supplied through a transformer that performs 
functions of galvonic isolation. In application 
If you go to the magazine you will find a simple 
ZX-MODEM program which uses 
transmission format from 600 to 1200 baud.       
 The program provides execution of two 
commands.                                   
 The first one is TRANSMIT, it transmits the samerequired number of bytes.                 
                                          
 The second is RECIVE, according to it some 
second number of bytes.                  
 It is worth noting that this program 
written exclusively for the 48 Kb model. 
Usage example:                     
 If you need to transfer a block of data with 
addresses 40000 and length 2000 bytes, then 
enter the command                           
                TRANSMIT 40000,2000       
                                     
 And when you need to receive information, dial 
the address where it will be placed        
                                     
                RECIVE 30000              
                                     
 Basically this program is suitable 
only for testing the modem, not for 
comfortable work.Currently local 
The E.C.Studio group is developing a package 
programs for organizing an electronic network 
in Neftekamsk and its surroundings.Perhaps there are already people in the city who know each other 
with problems of lack of required software and 
knows how to resolve them, we will be glad 
get acquainted with your ideas and advice.  
Well, in general, that's enough for today, but for those 
who wants to get a modem below 
Here is a schematic diagram of ZX-MODEMa.      
                                          
Р.S.                                      
                                          
 ATTENTION!                             
Keep in mind that if after exchanging data 
If the switch is turned on, then the TV 
the background line will be busy all the time.      
 Telephone communication is established as usual 
way what a telephone app is used for 
parat.                                    
                                         
                                          
                                          
                                          
                                          
+--------------------------------+   
     | Schematic diagram of ZX-MODEM. |.  
     +--------------------------------+.  
       ...................................  
                                          
 List of elements.                    
 -------------------                   
IC1-74LSO1 (5SSLA8)                   
 IC2-LMЗ24 (1401UD2)            
ICЗ-74LSO2 (5SSЛE1)            
ICCh-74LSOO (5SSLAZ)            
                              
TR1 - KTZ102 R1 - 820 OM            
D1 - KDS22 R2 - 10 K            
LEDr- ALZO7 RZ - 200 K            
LEDg- ALZO7 R4 - 100 K            
C1 - 100 Nf R5 - 56 K            
C2 - 100 NfR6 - 62  K                
СЗ  - 10,0      R7 - 680 K                
C4  - 1Н5       R8 - 100 K                
                                          
C5  - 1Н8       R9 - 100 K                
C6  - 1   Нф    R10- 1,5 K                
C7  - 120 Пф    R11- 820 ОМ               
C8  - 470 Пф    R12- 1   M                
C9  - 1   Нф    R1З- 10  K                
C10 - 1   Нф                              
C11 - 100 Нф                              
C12 - 10,0                                
C1З - 10,0                                
                                          
Трансформатор.                            
 S= 0.3 sq.cm        
1-2 = 450 turns D=0.07 mm        
Z-4 = 450 turns D=0.07 mm        
5-7-6 = 2*250 turns D=0.07 mm        
            
                                          
                                          
                                          
                                          
                                          
                                          

                                          
                                          
 ABOUT THE BENEFITS OF "OLD" PROGRAMS       
----------------------------      
  Ruslanych & E.C.S 
                                          
 Let's say a few words about mons and gens 
`ah. Lately, it has become more and more frequent 
there appears to be an opinion that this package is larger 
notneeded by the modern user. Te- 
now TASM, MASM, ALASM, STS and others are in fashion 
These are sophisticated systems, and "DEVPAC" is 
lived his life, and in general, this is frank 
squalor.                                
 However, let us allow ourselves a few words in advance 
shield of programs that, despite 
prosperity, have already become a “classic”.          
 We understand that creative thought is not 
stands still. Practice has shown that in 
recently on the domestic market 
software appears that exceeds the parameters 
                                          
frames have foreign analogues. So, for example, 
TASM 4.1 allows you to create source code on 
expanses of all 42Kb of RAM, remaining with 
this on another page. It's good, but.. 
   But let's return to earth, Disk drive, RAM 
128K is good if possible... 
For many, it will be a dream for a long time 
all this.The vast majority of users 
drivers have a regular ZX-48K with a tape recorder 
nom!They cannot use any pre- 
properties of TASM 128, nor IS-ASSEMBLER. 
But they dream of programming 
nothing less!                         
 For them, GENS andMONS are a little 
or the only means of programming 
vaniya. But not only DEVPAC is alive 
Speccy user, to what has been said, you can 
add that development and resuscitation 
"old" programs continue. We are very 
I liked the assembler"ZEUS +" 
which was modified by Sergey Khantsis from Izhevs- 
                                          
ka. We can say that this is the best 
version of ZEUS from those that came to us 
I wanted to meet. It has 14 new co- 
mand. Among which there is the possibility of as- 
assembling a program to any address 
directly to disk - no more problems with 
free memory.                        
 A few more words about “old” programs. 
Did you know that the package "EDITAS" is wonderful 
but understands undocumented commands with 
halves of index registers IX and IY?  
And now remember: which of the sophisticated 
programs of our time are capable of this... 
                                          
 Procedure "FLASH"             
-------------------            
  Ruslanych (c) 1999  
                                          
 Recently, many demo-makers  
they useto decorate their masterpieces  
a rather interesting procedure that I  
                                          
named "FLASH". Its essence is  
that during any action the screen  
instantly inverted for a very short  
for a while, simulating a flash.  
The complexity of this effect lies in  
synchronize coloring to inverted  
PAPER and BORDER color.  Below  
the procedure simulates this effect.1 ; -= FLASH =-                           
2 ; by Ruslanich from E.C.Studio          
З ; (17.01.1999)                          
4 ;                                       
40   ORG   25000                          
50   ENT   $                              
60   DI    ;+                             
70   EI    ;+синхронизация с прерыванием  
80   HALT  ;+                             
90   LD    A,7 ;цвет PAPER                
100  OUT   (#FE),A                        
110  LD    HL,22528                       
                                          
120  LD    DE,22529                       
1З0  LD    ВС,767140  LD    (HL),6З ;цвет BORDER           
150  LDIR                                 
160  HALT ;+                              
170  HALT ;|                              
180  HALT ;+пауза                         
190  HALT ;+                              
200  DI                                   
210  EI                                   
220  HALT                                 
2З0  LD    A,0 ;цвет PAPER                
240  OUT   (#FE),A                        
250  LD    HL,22528                       
260  LD    DE,22529                       
270  LD    ВС,767                         
280  LD    (HL),7 ;цвет BORDER            
290  LDIR                                 
З00  RET                                  
                                          
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