Tandy 1000 Technical Reference Manual

Tandy 1000
inter
8259A/8259A·2/8259A·8
Technical Reference Manual
ABSOLUTE MAXIMUM RATINGS·
Ambient Temperature Under Bias. . ..... O°C to 70°C
Storage Temperature. . -6S·C to + 1S0·C
Voltage on Any Pin
with Respect to Ground - O.SV to +7V
Power Dissipation 1 Watt
'NOTICE: Stresses above those listed under "Absolute
Maximum Ratings" may cause permanent damage to the
device. This
is a stress rating only and functional opera-
tion of the device at these or any other conditions above
those indicated in the operational sections of this specifi-
cation is not implied
-------
160 ns
190 ns
D.C. CHARACTERISTICS rTA = ooc to 700C, Vee = 5V ± 5% (8259A-8), Vee = 5V ± 10% (8259A, 8259A-2)]
I
Symbol
Parameter
Min.
Max.
Units Test Conditions
i
VIL
Input Low Voltage
-0.5
0.8 V
VIH
Input High Voltage
2.0'
Vee +0.5V
V
VOL
Output High Voltage 0.45 V
IOL = 2.2mA
I
VOH
Output High Voltage
24
V
IOH = -
4OO
Ii
A
I
Interrupt Output High
3.5
V
IOH = -
1OO
Ii
A
VOH(INT)
Voltage
2.4
V
IOH = -
4OO
Ii
A
III
Input Load Current
-10
+10
IiA
OV ,;;VIN ,;;Vee
ILOL
ourput Leakage Current
-10
+10
IiA 0.45V ,;;VOUT ,;;Vee
ICC
Vee Supply Current 85 mA
IR Input Load Current
-300
IiA VIN = 0
ILiR
10
IiA
VIN = Vee
'Note: For Extended Temperature EXPRESS V'H = 2.3V
Test Conditions
+----+-- --~----------~
fc = 1 MHZ
---_ .. -----------<
Unmeas~ed pins returned to V
ss
A.C. CHARACTERISTICS ITA = O°C to 70°C, Vee = 5V ±5% (8259A-8), Vee = SV ± 10% (8259A, 8259A-2)]
TIMING REQUIREMENTS
~-----.--~----- -~- 8259A-8 -r 8259A -- 8259A-2t-- -----
Symbol Parameter --.f.. Units Test Conditions
~_ _----=-_~----=-=--__ ..Pt1I~"-+-I'.'l~¥in. ~ .!i~. _~ax. _ _
TAHRL AO/CS Setup to RD/INTAJ 50 =1~ 0 ns
TRHAX
AO/CS Hold aft;r FIT'l/INTA! -- - -5-- O~ - -a--+-- ;;;- ------
-f--_.-.. -~f- -. -+ --------
TRLRH RD Pulse Width 420 235 I 160 ns
f-.---- ---- - --f--- --~+-- - --f------
TAHWL AO/CS Setup to WRJ 50 0 0 ns
f----- - -------- -- -- 1----1-------
TWHAX AO/CS Hold after WRI 20 0 0 ns
1-- __ . __ 1---_ ---.., f- .. -l------ ---+------- ---f---.----_
TWLWH WR Pulse Width 400 290 190 ns
f----+-------~--------t---~+_-_+__-- . __ +-_--+- +--- __ +---_ - ~- .. ----
TDVWH Data Setup to I;'V~ ~o~_ 240 160 ns
~....,~~_ ,Eata Hold af'-e..'~~l_______ __ ~ ~-+_0____l-_-+_-o---+---+--n-~s I-----_~
TJLJH Interrupt Request Width (Low) 100 f---------. 19.~ __ ~ __ ~~ I---f-_
ns
~_ee_N_a.~
TCVIAL Cascade Setup to Second or Th"d 55 55 40 ns
f- ~-('-S_--la-ve_-O-n-'-ly:...) ------+---+---+----+----+----f-----I-- .. --+-.----.--
End of RD to next RD I
TRHRL En~NTA to next INTA within 160 160
an INTA
sequence only .-i---
TWHWL End of WR to next WR---------· I 190- f-~-90
2-134

Tandy 1000 Specifications

General

Processor	Intel 8088
Processor Speed	4.77 MHz
RAM	128 KB (expandable to 640 KB)
Operating System	MS-DOS 2.11
Manufacturer	Tandy Corporation
Release Year	1984
Storage	Single or double 5.25" floppy disk drive (360 KB), optional hard drive
Sound	Tandy 3-voice sound
Ports	Parallel, Serial
Graphics	CGA (Color Graphics Adapter)
Graphics Modes	320x200, 640x200