Tandy 1000
Technical Reference Manual
Memory DMA
OE'
19
~
eLK
15
Vi
OS
~
!
74LS244.
~~~~~A1~6!::=~
~
~
8USA19
17
~
AEN
04
~'
+5
....
2Q...
....j0GNO
..11-42
..11-31
..11-30
..11-29
,J1-2B
..11-45
..11-44
..11-43
U2 U3 U4 U4
~
~)-"'06'--------"'='"------{EC::)
~
U2
11~~'3
~2
O~5
g2
1~9
r--;===.;;::=~
825153
~~;~~~~~S~~:===~-----------t---------''=!
~
09
08
rl./
02
I I MR_ a
~6
RASllf
74LS32
RASO_
~
'4LS04
03
06
11
De
I
MWtt
0
17
RAS2*
~ASltf
~AAS2M
74LS04
'4LS32
I
A16
a
18
RAS3
~J
~06
HSCL
01
13
~
~:~GNO~~~::O
I
RAS3'
5H2
~
...
__
~_05
__
74_"_50_0
--+~_-_-_-_-_-_-_-_---!----,
VREFRE~
U
Ai
CAS*
~
...
-tSV2 l14
El
E2
-
L
~~EE=========~=1====l---'
+5V
~
A12
1
U6
09
L-----
R2
E3
E4
-=-
V
:~~
~
74LS2571":~~~=-~-SH-2
--""MA""o6"----<'
L
~=;=lE=======~___1-+---___1-~
FIRSTBO
~_
V/
A15
0
07
MAO?
~
~
YjI3A04
1
.g;
<5V
~
BUS.A12
08
~.2
A1
~--lt-------1111----I---I------l~~~~:~;
~~~~~[I~-=------ll--r----/
:~~
~
~:l1!~
SUSA13
06
'4LS244
1f14
Ai
A14
09
~6
~~
~~:~
~A='5~-~~"'~<::c74~LS26
~
"'-~+--~
SUSAoa
11
09
A08
U51
U51
~
0
Ug
18
,--------------
-=-
BUSA09
13
07
A09
IRtf>-~
~O~
03
~1~
a A04 0
825153
~I
BUSAI0
15
05
A10
IWw>-!--
~
~1---I-~'=Aig05~=~0~
~~~~~~~
A02
U10
1':C'07'+c~------'2==--~(SSHH
22~
aU5A::,
~~
,l~::0'
74lS00
741500
~~:
~
~
<5V
I
:~~
74LS257
~:
~MA02
M
1~LS74~2,
~
1r==t===~~==iIW~=~1
16
AOO
0
:if~~
12
0
PFl
Q
09
1374l50;051
04
r;::t====1===:tIR~:==~O
~
~
~
~
2
0
PRO
0~4lS74
I
A03
0
oa
r
r="-------'-
~
+5V
11
e
U
K
'
Q
2
N
oa
Aoa
12"'
0
J:9GNO
II
V
~
01
DACK3*
}
~I
,---- V - V
FOCDMACKW
:=::::
..11-
46
CLFI
,'-__
03
U12
06
SFiDY
~jA~OgL=ai'3t:
DACK1*
~
~1,=
5
4a
7
_
74l
U
S
2
04
Fl3
13
OMACLK~
C~LOR,
:~~
~~
~
A02
L-.--
---1
;'U
U11
~
U2
~3
DRG3*
----l'"""""""',J1
47
,J1_5B
...........
DMATC
09
11
04 03
'~======+4~,-----~~-W
~
FBFOC~---X
-
BU5A04
g~
74LS244
~:
A04
~--+---+-l---,
"-
:;5V
R4
1
~
-
I-<
OMAelK
ORO
1>
~:=
;;
~~=~~
:~~:~~
~;
rc~~;~~~~~t===::-j
Lvv---J
,J1-~5~
BUSA07
04
f--1-"~6-=AO",-7
__
---../
_
r---+_+++----------+++
J
/
/ I
~~~~~~:W
D
..11-
52
~~=6:
~
OSC
+5V
~~
~HSCLK
0
U13
15
OACK3
A
r--Ittt==========t+~/--W------l--+-J,.------~
'---'"
..11-
50
,J1_53'-JBREGM
~~
~u22
f-"0~1
__
+_+---------'11
~
B237
14
FDCOM
C ( I
U14
19
~
L~===~~~O~
~~=:/rr+----+-+--+-l-----------t-+-t---t--'
~
7415373
"'~~'----------<
19
74LS04
1
16
OOQ3*
~
~
~~~
12
~
:~
~g~ARO'J
~
~~~
~;
~
~~!~~~F~~cs~~~'~===±±±±=========±i±=~
__
~
~
I~:~~====~:::::
(BUSA14
0£A-4
0GNO
~~~
~
ii=-<AosTa
r---+-+++---
,3
-------+++-------t--+-h
V
::::;-
~~
AbO~2=====~t==========~!==jO
~30~0=00-----t---++++--+-L~["'1
>~----_++_+-----_+-+_+--f--"""=~
~
:~~~
;
l~~
~~~
~
74LS04
.--
-----,
~~~U:======E==========:E=Ei;==D;
I~~
~~;
~
~
I
:~~~
~
l~~
~~~
~
AU
DMAAEN
.-t
74~~~2S
""b~~I-------<
At-;0~3======:;t==========+++++4=+1~0~
~
~
""oa;----+---<
t-' I I "
~~
11
~
:r-e--%
~V
~~
~GND
,J1-S1
,,J1-10
,,J1-33
,J1-15
..
..11-14
••
11-13
••
11-12
,..11-11
..11-19
,J1-1B
..11-17
..11-16
..11-23
..11-22
..11-21
..11-20
..
11-09
,J1-0B
..11-07
..11-06
..11-05
..11-04
..11-03
..11-02
~
(
I
y
Ie2
Ie3
Ie4
Ie5
~e6
Ie7
lea
Ie9
~C10
IC11
IC12 IC13 IC14 IC15
IC16
IC17 lC18
II
Ie1
-}I
I I I I I
T
I I I
T
T
I
I I
T
I
T
~002
~004
r/
005
SH
2
006
r
80002>0
r
...
r