Tandy 1000 Technical Reference Manual

Tandy 1000
8253/8253·5
Technical Reference Manual
ABSOLUTE MAXIMUM RATINGS·
Ambient Temperature Under Bias
Storage Temperature
VOltage On Any Pin
With Respect to Ground
Power DISSipation
0°Ct070°C
65°Cto +150°C
05 V to +7 V
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 lunctional opera-
tion 01 the device at these or any other conditions above
those indicated in the operational sections 01 this
specification is not impliec. Exposure to absolute maxi-
mum rating conditions lor extended periods may al/ect
device reliability.
D.C. CHARACTERISTICS (T A = O°C to 70°C, Vee = 5V c!: 10%) •
Symbol paramete! ~-I M~. t.... ".-"·t- ~ - __ Test Conditions -
:~-~:,:~~::::~:. - =-~_: ;- I-v~:;:e, L~ __ N:"'=: _
f-----VQ~_~_':'.:P~t ~~h_ V~o~lta~g~e ~ -~ _~ 4 t V- ~ !'J<'te2 - -----1
I'L Input Load Current _ __t~~ _~IN = Vee to OV
IOFL Output Float Leakage t10 _.1. IlA VOUT - Vee to 45V
Icc Vc:.c SU~IY CU~~~ - ~ 1 _140 - j m~_ __-~=--- - ~- ,
CAPACITANCE (TA = 25C, vee = GND = OV)
Symbol
Parameter Min.
Typ. Max.
I
Unit
T est Co nd ilio ns
C,N
I nput Capacitance
10
i
pF
fc
= 1 MHz
i
--_.-
-~---
C'iO
110 Capacitance
20
pF
Unmeasured pins returned to VSS
A.C. CHARACTERISTICS (TA'= OC to 70C Vee 5.0V" 10%, GND .C OV) •
Bus Parameters (Note 3)
READ CYCLE
,-
.~-~-~----~.-
8253 8253-5
f----
Symbol
Parameter
Min. Max.
Min. Max. Unit
tAR
Address Stable Before
READ
50
30
Address
Hold Time for READ
--._.-
tRA
tRR
READ Pulse Width
400
300
tRO
Data Delay
From READI']
300 200
tOF
READ to Data Floating
25
125
25
100
--
------
1---
. c-
-c-
tRY
Recovery Time Between· READ
/is
and Any Other Control Signal
6-147
AFN-C0145C

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