************ ********* PLANET SHELEZYAKA
Parallel on KR580VV55A
(C) Alfa Studio
(C) V. Kazakov
Today I'll introduce you to the remarkable development of
Alfa Studio, which was once published in the Belarusian
newspaper ECHO # 5. Unfortunately, CD with this great
newspaper, I ruined, having had only redraw the circuit, so
talk about the finalization of myself as I can.
A few words about the chip KR580VV55A. VV55A
is a device for parallel transmission of information between
the microprocessor and peripheral devices, and contains three
8-bit channel I / O A, B, C. Channel C can be represented in
the form of two 4-bit input / output channels to which access
is made as to the individual independent channels. Peripherals
are connected to channels A, B, C, and the connection to the
microprocessor by using the data bus through data buffer.
In the Spectrum with a device that collected on
KR580VV55A chip can be easily solved problems connecting the
printer, Kempston joystick, video port, Programmer, and many
other devices.
In order to collect the proposed scheme, you
except VV55A, need two circuits - the inverter, for example
555LN1 and decoder 555ID4. VV55A desirable to put on the
socket. Between the legs 555 chipset series, which fed the
voltage power needed to solder one capacitor 0.033
- 0.33 microfarads.
All signals are fed to the scheme, if you do not
system connector, taken from the findings of the
microprocessor. On the scheme after the name of the signals in
parentheses are the numbers legs Z80, corresponding to these
signals. In this case, pripaivaya guides to the processor, you
should be very careful not to burn him.
In conclusion, I want to give information about the addresses
used by chip VV55A channels in this scheme:
A - # 1F
B - # 3F
C - # 5F
RUS - # 7F.
+5 V
26
/ 34 4
To the data bus D0 IOP A0
Z80. . 3,2,1,
27. . 40,39,38,
D7. 37
9 A7
A5 (35) A0 18
8 B0
A6 (1936) A1. .
35. .
RES (1926) o RES. 25
36 B7
o / WR 14
5 C0
o / RD. 15,16,17,
6. 13,12,11
DOS o / CS KR580. 10
VV55A C7
7
1
/ IORQ o E1 DC D0
(20) 2
/ WR (22) E2 00
June 13
A0 (1930) D1 01
3
A7 (1937) D2 02
15
/ RD (1921) G1 03
14
/ IORQ (20) G2 D1
10
10
11
12 (c) Alfa Studio
K555
ID4 1913
PS. By the way, my Scorpio this thing, and indeed the previous
one, collected by several other scheme, for some reason does
not work ...
