Shadow RAM controller (c) Zhovtonoga Igor. 2001 ________________________________________ 1. Basic functions. This controller can work: a) as cache memory; b) replace system pages - new ROM with downloadable firmware. In bu- in the future it will be possible to perform the functions non-volatile RAM disk. Used as RAM There is a CMOS (CMOS) chip with a volume of 32 or 128 kilobytes (D8). 2. Description of work. In this design, the cache is locked programmatic "opening". The block works alignment through element D2.1 and turns on/ disabled by software. If afterdownloads to cache RC 1.96 or Quick 2.6 install lock program TEST4.30, etc. will show no cache, the XLC v3.5 program will work, and when pressing S1 will launch COMMANDER from ke- sha. When "opening" the cache, trigger D3.1 is installed is set to "0" at the /R micros input circuit D4 comes "1", outputs of the microcircuit D4 go to Z-state, to address inputs (A14-A15) of the operational chip memory (D8) is supplied as units. * Numbering of digits, addresses, pages RAM, ROM starts with number "0". Thus, the cache is always allocated last page of the chip used RAM. S1 - momentary button, diode anode V1 is connected to the "MAGIK" button. Such a connection is possible if other The output of the "MAGIK" button is connected to body If this is not so, then you can connect diode V1, replace V2 with jumper and put a button in place of S1 with commit, then the cache will be accessed occur by pressing "MAGIK" when closed position S1.Other implementation options are also possible hardware cache access. To work in system replacement mode ROM bootable RAM needs to be made loading the corresponding RAM pages controller and also program controller ports. Microcircuit D4 (IP26) performs programmable decoder functions pages of system ROM and controller RAM. This chip contains four 4-bit register (l.1). Writing to the registers of the D4 microcircuit is provided as a port with addressm 62455 (FЗF7). The assignment of the bits of this port is as follows: blowing: D2 , D6 , D7 - set RAM page controller projected to addresses #0000H- #ЗFFFH . If the RAM capacity is 32 kilobytes - digits D6, D7 are not taken into account. Corresponding the effect of these bits and address inputs D8 RAM chips are: D2=A14 : D6=A15 : D7=A16 . D3 and D4 - setting the system page ROM that needs to be replaced. In the computers "PROFI" and "PENTAGON" correspondence of digits D3, D4 and pages The ROM is as shown in Table 1. Digits ! Conclusions! port !system= ! Tab.1 62455! new ROM! ! ! D3! D4! 27! 1! ========================== 0! 0! 0! 0! 0 pages ========================== 1! 0! 1! 0! TR=DOS ========================== 0! 1! 0! 1! BAS128 ========================== 1! 1! 1! 1! BAS48 In computers of other models, the location ROM page firmware may be different. D5 - gives a command (when set to " 1 " ) connection page RAM control- lera specified by digits D5-D7 instead ROM pages specified by bits D3, D4 port 62455. When D5 is set to "0" it is possible write to the RAM page of the controller tsirovonnuyu inaddresses #0000H-#ЗFFFH . Blo- The entry in the controller RAM must be assigned be disabled. Other settings are made by port with address 64503 ( FBF7 ) . The purpose of the bits of this port is as follows: D1 - "0" software lock connection to cache memory. D2 - "0" RAM read blocking controller D3 - "1" blocking writing to ports controller Unlocking - by turning off food . D4 - "0" blocking writing to RAM controller Ability to write to cache remains . After turning on the power, all digits port 64503 is set to "0". If you plan to use a cache-pa memory to the last page of the controller RAMничего не загружается Please note: 1-year-old slightly larger size2-я часть схемы это сам контроллер
Pantera>By the way, if you don’t have mikruhi 15ZZIR26 in the CIS equivalent, then don’t be too upset, because... try it look for her among the bourgeoisie with that name type (74)(A)LSb70. As is known, one drill- Zhuyskaya mikruha is more reliable than our 3. Here for example, I try not to use take away our mikruhs, because they no longer have that whose quality is the same as in the USSR. Bought a bunch burnt 38bDX boards and all sorts of controllers took a gas burner and went ahead :-). 3. Programming Let's assume that we have installed D8 chip with a capacity of 32kb and we need download firmware "GlukS.3k" instead of BAS128 and RC 1.96 in cache. 10 OUT 62455.0 ! In all categories of all 20 OUT 62455.8 ! microcircuit registers 30 OUT 62455.16 ! D4 write "0" 40 OUT 62455.24 ! 50 OUT 64503.16 ! Disable blocking ! records in RAM 60 RANDOMIZE USR 15619 : REM : LOAD "GlukS.3k" CODE 0 70 OUT 62455.48 ! Instead of 2nd page ! ROM (BAS128) is now ! will be connected ! 0th page ! Controller RAM 80 OUT 64503.6 ! Disable blocking: ! a) software ! "opening" cache ! b) reading RAM ! controller We launch the program and after pressing "RES" instead of the BAS128 screensaver wewe can see the menu "GlukS.3k". Turn on re- press clear cache, launch RC 1.96, by pressing key "i" . Again press "RES" and exit Option "Exit CH" launch RC 1.96. Another sample program to download firmware "048_ROM" instead of VACH8 and "dos13f" in place of TR-DOS: 10 OUT 62455.0 20 OUT 62455.8 30 OUT 62455.16 40 OUT 62455.24 50 OUT 64503.16 60 RANDOMIZE USR 15619 : REM : LOAD "dos13f" CODE 0 70 OUT 62455.12 80 RANDOMIZE USR 15619 : REM : LOAD "048_ROM" CODE 0 90 OUT 62455.40 100 OUT 62455.32 110 OUT 62455.60 120 OUT 64503.4 Program for operating the controller in real time RAM disk mode is currently not written sana 4. Assembly. Since the printed circuit boards are factory-made cooking assembled or empty for this there is no controller and does not “really” anticipate you will have to assemble it on the board own production or on a breadboard printed circuit board. "home" technology production of boards has been repeatedly described - appeared in literature. From the "bourgeois" devices for making printed materials boards are now on sale:special "Water-resistatn" marker and varnish-photore- zist POSITIV 20 . But the use of a breadboard is still more convenient due to the possibility of simpler making additions to the diagram. 5. Setup. Instead of what is indicated on the circuit diagram ME 1533 series chips can be used Episode 555. The structure was manufactured in the 1st production specimen and therefore statistical data about the performance of this scheme with other details are missing. Actually, adjustment may not be necessary - xia . How to signal a ROM lock(Block ROM) depends on the computer circuit. You might have to experiment with this. to rove. Universal protection against failures is installation on interlocking power circuits capacitors literature: 1. "Logic ICs KR1533 KR1554" I.I. Petrovsky and others. March 24 - May 10, 2001 P.S. The design is made comparatively recently and most likely this version is not final, but decided to publish this development because it works quite well capable . __________________________________________ Pantera> As a metal worker, I want to note that it'll be a cool thing. I'm this one I’ll definitely make myself a controller, and once vodka will be accompanied by Nemo-bus. Well, for those who does not have a screw in IS-DOS is completely noticeable specifically. Write a driver and enjoy IS-DOS on a RAM disk.Also, a little advice: Instead of a RAM chip 62256-621024,you can use 61256-611024.These mikruhi stand on IBM compatible machines in ka- honor cache memory. Yes, and there is a burnt mother 3 UAH And one microcircuit is 62256-8 UAH 621024-21 UAH. So draw your conclusions. Nap- My example costs 61256 and everything is OK.
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