Hardware - System P3U Quorum, pros and cons.

                                
                                
                                
                                
                                                                
                                                                
(с)Highlander (Max Melnikov, 500:3432/13).                      
                                                                
           +----------------------------------------+           
           + Системное ПЗУ Кворума, плюсы и минусы. +           
           +----------------------------------------+           
                                                                
    Начну  сразу,  без  рaссусоливaний.  K плюсам можно отнести:
- Загрузчик с диска по сбросу (CP/M или TR-DOS) - In mode 48 setting BASIC ROM (proprietary/quorum,
 working with normal/turbo tape)                                 
- Built-in tests (memory, tape recorder, colors, coprocessor)     
- NMI service                                                    
    Cons:                                                     
- When the TR-DOS disc is detected, TR-DOS starts in
 48th mode.                                                 
- Test memory not tests the first 8 kB of the fifth page, stack
 located in untested part of the fifth page, and active
 is used.                                                 
- With NMI on stack lay down: return address (nothing wrong with that
 do it no, because  this is managed by the processor), AF registers,
 BC, DE, HL. If there is no resident in memory, almost completely
 the 6th page is killed and returning to the interrupted program is only
 in 48th mode.                                               
                                                                
    I I am writing alternative firmware, briefly aboutwhat's in it
will include:                                                  
- Test of all memory.                                             
- Loading from disk, and if a TR-DOS floppy disk is detected,
 there will be a menu in which selects the launch option (TR-DOS
 48/128, or built-in boot 48/128). If the disk is non-standard
 (not TR-DOS and not CP/M) it is considered that the disk is autorun,
 select TR-DOS 48/128 only.                                   
- If ROM capacity is 128 kB, then there will be a ROM disk of 64 kB (what is there
 I don’t know how to write it down yet)                                         
- By NMI transition to the resident if there is one, if not, then something
 type MagOS`a on Scorpio (6 128 programs if 1 MB, 2 if 512,
 if 256 then none). You can also take off three-sevenths
 pages (such as STS, HELP Roshchina, etc.)             
- If it is CMOS, then all settings are saved in it.           
                                                                
     Here some citizens don’t know how to nail STD (shade,
hanging on NMI by a resident), So it’s very simple:                   
    XOR A                                                      
    LD BC,#7FFD                                                
     OUT (#00),A                                                
    LD A,#40                                                   
     OUT (C),A                                                  
     XOR A                                                      
     LD (#C066),A                                               
     LD A,#10                                                   
     OUT (C),A                                                  
     LD A,#A8                                                   
     OUT (#00),A                                                
 и  все,  STD не вызозовется, только после этой процедурки будет
вкюченa  0-я страница, a комп в 128-ом режиме. Чтобы (вдруг кому
надо) получить 48-ой режим, в строке LD A,#A8 нужно заменить #A8
на #Е8 (зaблокируется порт #7FFD).