Apple Transwarp 用户手册

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Software Control
Programmers can also control TransWarp from within their programs by writing a 
specific value to a certain memory location.   This location, expressed in 
hexadecimal notation, is $C074, and in decimal notation, 49268 (-16268 Integer 
BASIC complement). The valid values which can be written to this location are 0, 
1, or 3. A zero enables the maximum hardware default speed. A one will cause the 
TransWarp card to run at 1 MHz. Writing a three will disable the TransWarp card 
completely and pass processing control to the Apple’s processor until the 
TransWarp is again activated by cold-booting the system. The following example 
Applesoft BASIC program line will slow the TransWarp to the 1 MHz clock rate.
]10 POKE 49268,1  
Accesses to the Apple’s RAM and ROM are restricted to the Apple’s clock rate of 
1 MHz; therefore, on power-up, TransWarp loads the Apple’s ROM into its RAM, 
and uses the rest of its RAM to emulate most of the Apple’s main and auxiliary 
memory, running at accelerated speed. The Apple’s memory is used only for 
video display of text and graphics, which requires the 1 MHz rate. This can cause 
some video- intensive programs to run slightly slower than full TransWarp speed.
TransWarp does not use the memory cache-ing technique to increase     
processing speed. All processing in main and auxiliary memory is accelerated.  
This is a great advantage to users of memory expansion cards which install in the 
Apple //e’s Auxiliary Slot, such as Applied Engineering’s RamWorks and 
RamWorks II cards. All accesses to these cards are at TransWarp’s accelerated 
speed. Using RamDrive software to use the accelerated extended memory as an 
emulated disk drive, disk-access-intensive programs loaded to and executed   
from a RamDrive will run appreciably faster.
CP/M Software Z-80 cards which have their own memory and do not use the Apple’s direct 
memory access (DMA) bus, will function (at normal speed) with the TransWarp 
card active. Since processing for the CP/M software is being done by the Z-80, 
TransWarp’s 65C02 will not accelerate CP/M programs.
Some Z-80 cards use the Apple’s DMA bus to access the Apple’s memory. The 
TransWarp card must be deactivated before running CP/M software on Z-80 cards 
which do use the DMA bus. TransWarp can be deactivated during a CP/M cold 
boot by depressing the ESC key during power-up. (See the section entitled 
“Hardware Control.”)
TransWarp
                                                                                                              
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