Wallpaper #02 31 мая 1998

Железо

Iron - Passhipenie memory Tashkent 128.

        3. Extended memory for

               TASHKENT-128



 From the Editor:

  Finally, it happened! Now users Tashkent version may Spectrum
access to software for which you want more
128K of RAM. Especially because
Recent such programs has been
much more.

 This scheme is based on schemes
computer modifications proposed in
the electronic journal SPECTROFON
(N17, 18). Since these improvements
compiled for the computer PENTAGON-128
, Then immediately apply them to your PC
TASHKENT-128 is impossible.
 Changes to the scheme taking into account the peculiarities
TASHKENT PC-128:

 1. The procedure for connecting signals
computer to an additional
multiplexer control circuit RAM 512K
K555KP12.
 2. K555ID7 decoder with 6 diodes
replaced by a log. scheme in IMS LL1 and LA3,
signal is used with computer-# FD.

 The control board maintains the port # 7FFD
PENTAGON mode and ports # FDFD, # DFFD in
mode PROFI-ATM.
 In the transition mode 48 to the scheme
blocked by maintaining bank number
RAM.
 Control scheme is implemented on
separate two-sided board, drawing
which is given in the appendix.
 The schematic circuit diagram is not
is due to the complexity of its input (
if necessary, may be
recovered from the printed picture
Board).
 To implement the scheme will need PMI:
K555LA3, K555LL1, K555KP11, K555KP12,
K555TM2, K555LE1 (of 6 buildings)
- For management fees;
16 memory chips K565RU7 (
recommended with the letters B, I, K, and better
[SP-FON17]) - to implement 512
Kbytes.
 Poklyuchenie 512 to produce a better
two stages:
 1. Replacing the IC memory and eliminating
damage to the computer's motherboard,
occurred during this operation.
 2. Building and installing the control board
with further debugging.



 REPLACING THE MEMORY IC, the most dangerous (for PC)
operation, so it must be
done with extreme caution. Not
Take the time to pick up a handy tool.
PMI can be removed with a soldering iron with
Long, odnoryadovym tip (at
This staraytas less warm place
rations and raise a number of conclusions with IC
the first time), alternating otpaivaya 1 and
2-th row of the chip. You can do
vykusyvaniem ICs, removing the remaining
board of the findings soldering iron (in this
If IMS can not be deleted
use more ...)
 After carefully removing PMI
inspect the PC board and remove the raised
when you remove PMI, parasitic coupling (at
Beware of removing this right
compounds).
 Install IC RU7 instead of remote, when
This does not heat the findings of IC more
2-3s (preferably powered soldering iron
through the power regulator or through Latry)
 Combine the 1-st conclusions RU7 all in one
bus (better to use a hinged
assembly) and temporarily grounded.
 Connect through the RAS line rezestor 1
kohm to +5 V in. (3rd output ICs LN1
the right of the quartz crystal).
 Checking all circuit block RAM tester
enable kompyuter.Na screen after
passing an initial test SOS, dolzhno
menu appears SPECTRUM-128. When
failed the test, try soedinet
RAS line 4-th output RU7 through capacity
47-240 pF to ground (gently). Maybe
will increase the capacity or the number of
bypass capacitors near the IC
memory.
 After a successful test available to 128K of RAM
all even-numbered pages which do not
regenerated (the cause of failures
attempt to enter the program on or BASICe
boot from the drive, issue the command CLEAR
32767). Podruzit Try different
programs (eg RAM test, some
of them will show OK.).
Efficiency (possible partial)
part of the software indicates the proper operation
block RAM.



    CONNECTION SCHEME MANAGEMENT 512K

 Assemble the control board by drawing
in annex. Before
installing the IC be sure to check
fee to the closure of conductors between
themselves.
 Naznechenie signals and a computer FEES:

STROBE - the recorded signal at ports # XXFD
PORT - Port Selection # 7FFD or # FDFD,

       # DFFD
D0, D1, D6, D7 - Data Bus line CPU
A8, A9, A13, A14, A15 - the same name
CPU Address bus line
A8 '- served instead of A8
CPU - CPU to address memory (CPU = 0)
L / H - choose the senior / junior side
RAM addresses
B14 - video controller signal
RAM - the hook line to the 1-m pin. RU7
RES - Reset
BLOCK - disable 512K
 Necessary changes on the board
computer swap:


     DD20 (11c) <> DD22 (6c)

     DD21 (11c) <> DD23 (6c)

     DD22 (13c) <> A8 '(control board)
0> DD23 (13c)> B14 (control board)

     DD26 (1c) <> DD26 (4c)

 Location of signals on a PC board


     STROBE - DD26 (8c)

     RES - DD25 (1c)

     A14 - DD27 (13c)

     A15 - DD27 (12c)

     CPU - DD22 (15c)

     L / H - DD22 (1c)

     RAM - RU7 (1c)

 PORT, BLOCK output on connector
Keyboard pre-Division 2
terminals with an awl from a common bus.
 The remaining signals are removed from the IC ROM
(T.k.na many pay 4 IC ROM of 8
KBytes replaced by a capacity of 32
KB, the signals can be output from
free holes)


                           2

                    DD27 DD26 5

D D
February 2
1 0

                LOCATION

              INSTALLATION ROM
D D FEES
February 2 CONTROL
March 2