Tandy PC-6 User manual

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Toshiba America Information Systems, Inc. and Apple Inc. Exhibit 1012

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CONTENTS
SPECIFICATIONS . . . . . . . . . . . . . . . . . . ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
How To Open Upper Case ....... . . . . . . . . . ..... . . ... . . . . . ...... . . . . . . . . ... . . . . . 3
THEORY OF OPERATION . . . . . . . . . . . . ... . . ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . ..... . ... . ... . . . . . . . . . . . . . . . . . . . . . . . . 4
Interrupt Circuit
Keyboard . . . . . . . . . . . . . . . . . . . . . ..... . ...... . . . . . . . . . . . . ..... . . . . . . . . . . . . . . . 6
Power Supply ....... . . . . . . . . . . . . . . . . . . . . . . . . . . .... . . ...... . ... . . . . ...... . . . 7
LSI (Pin Functions) ........... . . . . ...... ... ..... . . . . . . . . . ..... . . . . . . . . . . . . . . . . . . 8
DISPLAY . . . . . . . . . . . . . . . . . . . . . . . ... . . ... . . . . ... . . . . . . . . ..... . .... . . . . . . . . . . . . . 9
TROUBLESHOOTING GUIDE . . . . . . . . . . . . . . .... . . . ...... . . . . . . . . . . . . . . . . . . . . . . . . 10
Test Programs . . ... . ........ . . ...... . . . . . . . . . . . . . . . . . . .... . . . . . . . . . ... . . . . . 11
Operation Check . . . . . . . . . . . . . . . ... . . . . ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
PCB ASSEMBLY VIEWS . . ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 19
PARTS LIST . . . . . . . . . . . . . . . . . . . . ...... . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . .. 20
Electrical Parts ..... .. . . . . . . . . . ...... . .... . . . . . . ... . . . . . . . . . . . . . . . . ...... . . . 20
Mechanical Parts . . . . . ....... . . .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
EXPLODED VIEW/DISASSEMBLY INSTRUCTIONS . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . .. 23
SCHEMATIC DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 24
Main I3lock . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . ..... . . . . . . . . . ... . . . . .. 24

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Display Method
Display
Calculation Range
Program System
Program Language
Number of Variables
RAM Capacity
Program Areas
Number of Stacks
Subroutine
FOR w NEXT
LOOP
Operators
Power Supply
Power Consumption
Battery Life
Memory
protection
battery
Auto Power-off
Ambient Temperature
Dimensions
Weight
SPECIFICATIONS
5 x 7 dot-matrix crystal
24digit, dot-matrix liquid-crystal display
i10'99 w :t9.999999999 x 10”
Stored System
BASIC
26 fixed variables, exclusive character variable and array variables
7520 bytes (system area: 672 bytes)
Maximum of 10 (P0 through P9)
8 levels
4 levels
12 levels
2 lithium batteries (CR-2032) for main frame
1 lithium battery (CR-1220) for memory backup
Maximum 0.07W
1) Continuous program execution: approximately 85 hours
2) Continuous display of 5555555555 at 68°F (20°C): approximately 200
hours or 5.5 months when unit is used 1 hour per day
NOTE: 1 hour includes 10 minutes of condition 1) and 50 minutes of con-
dition 2)
Approximately 2 years (with main batteries installed)
Approximately 6 minutes
32° F to 104° F (0°C to 40° C)
3/4"H x 5-5/8"W x 2-3/4"D (18 mm x 142 mm x 71 mm)
5.8 oz (165 g), including batteries
How To Open Upper Case
Tweezers
1. Insert the tweezers into the back of the upper case.
2. Move tweezers gently in the direction indicated by the
arrow in the figure below.

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THEORY OF OPERATION
Block Diagram
DOT—MATR|X DISPLAY
5 x 7 dots, 24 digits
a7’\za12, d7’\zd12 a1r\,a5, d1r\,d5
b7'\zb12, e7’\ze12 b1r\,b6, 314,55
c7~c12, RONR14 c1’\zc6, R0'\zR14
RAM IC3
Ks2’\uKs10 '<mW'<m12
KEYBOARD KEYBOARD
HM6264ALFP
ADO-AD12
CS3-CS6
I00-I07
26-3671
26-3651
26-3652 26-3652
NOTE: Only one of 2 options can be connected at a time.

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LSI
Main CPU
HD61747B20 BASIC control, Key signal input/output (lower keyboard), 1st to 6th digits and
13th to 18th digits display control.
Sub CPU
HD61747B25 Calculation, I/O control, key signal input/output (upper keyboard), 7th to
12th digits and 19th to 24th digits display control.
Gate Array
MB64H193 Interface between CPU and RAM, buzzer control.
RAM
HM6264ALFP-50‘ Stores data and program. RAM has 8K bytes (64K bits) capacity and contains
a self-control circuit.
LSI ROM
CPU (Main)
H D61747 B20
CPU (Sub)
H D61 747 B25
RAM
HM6264ALFP-50
113024 bits 1896 bits
113024 bits 1896 hits
65536 bits
226056 bits 69328 bits
Input Buffer
Code Buffer
Z
— Users Area
--
M FT
P3T
P7T
Communication Buffer
2
GOSUB STACK
DISP Buffer
FF —
¥.:'i:; FOR NEXT

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Buzzer Control Circuit
There are 3 ways to operate the buzzer:
Key input, BEEP O, and BEEP 1
Mode BEEP 0 BEEP1 Key Input B2
Frequency 0.9 kHz 4.55 kHz 4.55 kHz 31
Time 110 msec. 110 msec. 11 msec. MBMH193
Interrupt Circuit
0 interrupt circuit for the clock pulse when VDD2 drops.
1. When the power is on, VDD2 is "L" level.
2. PG2 through the IC and 26th pin of the CPU receive PG2.
3. When VDD2 drops, the output of the IC becomes “GND” level and the CPU does not receive
PG2.
PG1
HD61747B25
0 Interrupt circuit for the voltage of the Gate Array and options when VDD2 and SW drop.
1. When the power is on, VDD2 and SW is "L” level.
2. VDD2 for Gate Array and VDD4 is also "L" level.
3. When VDD2 drops, VDD2 for Gate Array and VDD4 becomes ”GND" level and stops the op-
ration of the RAM and options.
sw
VDD2(from IC 4) — VDD4
VDD2(from IC 2)
HD61747B25 controls the upper keyboard.
K52 ‘
HD61747B2 - K53“’K‘°’8
K59, K510
HD61747B20 controls the lower keyboard.
Keyboard
HD61747B2 K"‘5“’K””°
Km11, Km12

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Power Supply
VSS1 Power supply voltage for TC4071 BF.
VRAM Memory used to keep the voltage for the RAM.
V1~V5 LCD drive voltages. Voltage is generated by connecting the external resistor to VDD2.
VDD1 Power supply for the CPU, RAM and options.
VDD2 Stays VDD1 at power—on. Goes to GND at power-off or APO (auto power—off).

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LSI (Pin Functions)
IC1, HD61747B2O
lC2, HD61747B25
o°ol3r°3'R$§§"§§KE$°m‘3‘cB%$
A A A A
E E’ E
1 64
2 63
3 62
4 61
5 60
5 59
7 58
8 57
9 58
-[Q 55
11 54
12 _ 53
13 _ 52
14 > 51
15 _ 50
16 _ 49
17 _ 48
18 _ 47
19 46
20 _ 45
21 > 44
22 b5 > 43
l\)|\) 4300
0.0
0101
VV
-54> an
IC4, MB64H193
1N4
5
19
Signal Name
D1, 2, 4, 8
INT
KM’\zK1
SW
V5’\;V1
PG2, PG1
R15’\IFl7
GND
CE2
CE1
VDD1
VDD2
Signal Name
Function
Data in/out (D1, D2, D3, D4)
Interrupt signal from RAM
Key signal for keyboard
Switch signal. GND at switch
"OFF” and VDD1 at switch
MON!!-
Display voltage. Divided vol-
tage from VDD1.
CPU internal clock
Display signal
GND
Chip designating signal.
Select RAM or other devices
Select RAM or other devices
Power source
VDD1 output from the LSI.
VDD1 at switch "ON” and
GND switch ”OFF".
Clock pulse
Operation signal
Function
I00, I06
ADO
I07
AD1
VSS
AD2, 10, 3
OE
AD4’vAD12
VDD
RW
CS6’\ICS3
CS2’\uCSO
B1, B2
S2
VSS
S1
E
OF
Data in/out
Address signal
Data in/out
Address signal
Power source
Address signal
Output enable
Address signal
G ND
Read/write signal
Chip enable signal
N C
Buzzer signal
G ND
VSS
G N D
NC
Data in/out
Operation signal
Clock pulse
Power source
Chip enable
G N D
Data in/out

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lC3, HM6264ALFB-50
Signal Name Function
NC NC
A12'\:AO Address signal
I/O1’\z|/O3 Data signal
GND VSS terminal
I/O4’\zl/08 Data signal
CE1 Chip enable
A10 Address signal
OE Output enable
A11, 9, 8 Address signal
CE2 GND
R/W ‘ Read/write signal
vpp 1 GND
DISPLAY
Numbers and characters are displayed in 5 x 7 dots.
Following is an explanation of a dot—matrix LCD.
3 I9
“_’.
IQ
000-3
E—0000000
3
1
N
2
“_’.
DDD-3
Lower electrode Lower electrode
‘°1J
la:
d 0 0000000-
;—0000000 0
U 0000000—— -—0000000 N
0000000 N 0000000-
I
I I
0000
0000000—2
- 0000000- Q 0000000-
;—0000000
U 0000000—2
_—0000000 N
0000000 N 0000
0000000——
g—0000000
0000000-
0000000 g—0000000
DT? 0000000-
1) :0
tone
Upper electrode
5
Upper electrode
13.1.’ 1131113
glsl
UCIUUDDD
CIDUDUUD DCICIDUDU
DUCIUCIDCI DDCICIDUU
DDDEICIUU
DDDDDUD U‘-'UCl0ClClDD
UDUUCIDCI
CIDUCIDUU CIUDUDUU DDCIDDUU
CIDUUUDD
CIUDCJCIUD
DDDDCIDCI
UDUDDUD
iii”
U1 3
Left-half 12 digits Right-half 12 digits
81 d1 b1 31 On the upper electrode of the LCD, common signals RON R6 and R8~ R14
are applied horizontally while other signals a1'\»e1 to a12'\:e12 are applied
I II II
Egg?!-1+3? vertically on the lower electrodes as shown in above figures.
I&I¢I*I II
In the left figure, the upper—right corner of the dot is displayed when a vol-
_ __ tage difference exists between signals R0 and a1. The CPU outputs the dis-
play signals to the LCD display.
CPU HD61747B20 controls the 1st to 6th and 13th to 18th digits of dis-
play, while HD61747B25 controls the 7th to 12th and 19th to 24th digits.

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TROUBLESHOOTING GUIDE
Symptom Cause Solution
C No display at all. Weak batteris Replace the batteries.
Poor battery contact Clean the battery and contact spring.
Lift the battery spring.
Peeled heat seal Replace the heat seal.
Broken heat seal Replace the heat seal.
LCD (CA51-TS) Replace the LCD.
LSI (HD61747B) Replace the LSI.
A certain segment(s) Peeled heat seal Replace the heat seal.
cannot be displayed.
Broken heat seal Replace the heat seal.
LCD (CA51-TS) Replace the LCD.
LSI (HD61747B) Replace the LSI.
Calculation impossible. LSI (HD61747B) Replace the LSI.
A certain button does not Poor key contact Celan the contact pad on the PCB and the
function. key contact rubber.
Broken PC line Connect the PC line.
Peeled heat seal Replace the heat seal.
LSI (HD61747B) Replace the LSI.