Pioneer PX-7 User manual

($ PIONEER
Service
cTVIanual
CIRCUIT &MECHANISM
DESCRIPTIONS
REPAIR & ADJUSTMENTS
ORDER NO.
ARP-683-0
PERSONAL COMPUTER
MODEL PX-7 COMES IIM TWO VERSIONS DISTINGUISHED AS FOLLOWS:
Type
HE
HB
Voltage
AC220V, 240V (switchable)
AC240V, 220V (switchable)
Remarks
European continent model
United Kingdom model
RF OUTPUT
G/PALUHF 36 ±1ch
l/PAL UHF 36 ±1ch
•This service manual is applicable to the HE and HB types.
CONTENTS
1. SPECIFICATIONS 2
2. PANEL FACILITIES 12
3. DISASSEMBLY 21
4. PARTS LOCATIONS 23
5. EXPLODED VIEWS AND PARTS LIST 25
6. PACKING 28
7. CONNECTION DIAGRAM 29
8. SCHEMATIC AND P.C. BOARDS
CONNECTION DIAGRAM 31
9.
ELECTRICAL PARTS LIST 44
10. ADJUSTMENTS 48
11. INSPECTION ROM INSTRUCTION
MANUAL 53
12. BLOCK DIAGRAM 69
13. CIRCUIT DESCRIPTION 73
PIONEER ELECTRONIC CORPORATION 4-i. Meguro i-Chome, Meguro-ku, Tokyo 153. Japs
PIONEER ELECTRONICS [USA] INC. P.O. Box 1760. Long Beach. California 90B01 USA.
TEL: [BOO] A21-1AOA, [BOO) 237-OA24
PIONEER ELECTRONIC [EUROPE] N.V. Keetberglaan 1. 27AO Beveren. Belgium TEL: [phone]
PIONEER ELECTRONICS AUSTRALIA PTY. LTD. 178-1 BA Boundary Road. Braeside. Victoria 3195. Austral
TEL: [03) 5BO-9S11 FZ ©OCT. 1985 Printed in J;

PX-7
1. SPECIFICATIONS
1.
1
CPU 8-bit Z80A (3.58 MHz clock)
Memory RAM 48K (including 16K video RAM)
ROM 40K (32K MSX BASIC, 8K P-BASIC)
Display Text SCREEN 0: 40 X24 (default 37 x24)
SCREEN 1: 32 x24 (default 29 x24)
Graphics
resolution 256 x192 dots
Colors 16 colors
Sprites 256 sprites
Output PAL composite video output (16 colours)
lVp-p/75 fi
RGB output (8 colors), TTL level
HB model: I/PAL/RF output (16 colors
with sound)
HE model: G/PAL/RF output (16 colors
with sound)
UHF 36 ±1ch, 74 dB/tV/75 0
Screen control Computer mode
Superimpose mode
External video mode
Keyboard Type Separate type, full stroke, 76 keys
Cylindrical step sculptured key tops
Facilities Alphanumeric: 48 keys
Control: 20 keys (with 4cursor keys)
Function: 5keys (10 functions selectable)
Screen mode control: 3keys
Cable 1.5 mwith 13-pin DIN plug
Sound Source 3voice (8 octaves +1noise, 8~
envelopes) C°T“;
Ivoice (key click sound) }sound
External stereo audio input signals
150 mV/50 kfi
Output Internal speakers (stereo)
Headphones (stereo)
Line output (stereo), 150 mV/1 kfi
Mixing control Computer sound mixing level control ±15 dB
Master volume control
Externa! sound muting control
Interface System control Laser Vision Player, component display,
audio system remote control ports
Cassette recorder Baud rate: 1200/2400 baud (software select)
FSK signal
Printer Centronics standard, 8-bit parallel port
Controller Ports for 2joysticks, tablets, paddles,
trackballs, etc.
Cartridge 2MSX cartridge slots (slots #1and #3)
Power requirements 220/240 V±10%, 50/60 Hz,
Power consumption: 37 W
Operating temperature 5—35 deg.C
Dimensions Main unit: 420 (W)x 323.5 (D)x70 (H) mm
Keyboard: 420 (W)x 171 (D)x47.5 (H) mm
Accessories •Warranty card
•RF cable (2 m)
•Instruction manual
•BASIC reference manual
•P-BASIC reference manual

1.2 BLOCK DIAGRAM

1. 3MEMORY MAP
Hexadecimal addresses
0000|
User
area
MSX BASIC
ROM
Program area
(text area)
Variable area
Array variable area
Character string area
File control block
«Area in which programs with line
Inumbers are stored.
pVariable area
With character variables, the pointers
(string descriptors) to the character
strings provided are stored in this area.
•Array variable area
If the array variables are character
types, the pointers to the character
strings provided in the character string
area are stored in this area. The area
itself is secured when DIM statements
eexecuted or when arrays with 10 or
less accompanying characters are used.
•The free area is not used. Its size is
'determined by subtracting the stack
area, variable area and program area
from the user area. It can be sought by
the FRE function.
•Stack area in which BASIC returns and
addresses are saved when FOR-NEXT
>r GOSUB statements are executed.
fArea in which character strings includ-
ed in the character variables and array
variables are stored. The size of this
area is the size designated by the
CLEAR statement. An area of 200
bytes is secured if there is no designa-
tion with the CLEAR statement.
Area used with file input/output. It is
secured in line with the number
designated by the MAX FILES
statement.
»The upper limit address can be set to
F380 or less by CLEAR and so it is
possible to provide an area separate
from the work area which the user can
use freely for machine language
routines, etc.
>Area in which BASIC is used.

PX-7 Memory Configuration
Address Slot #0 Slot #1 Slot #2 Slot #3
Expansion
I/O register
Expansion
slot
(rear of unit)
1.4 I/O MAP
(1) I/O address allocation
RW Details Remarks
&H98 WData write into TMS9129NL
VRAM or
RData read from equivalent
VRAM
&H99 WCommand, address set
RStatus read
&HA0 WAddress latch AY-3-8910
&HA1 WData write or
&HA2 RData read equivalent
&HA8 WPort Adata write 8255A or
RPort Adata read equivalent
&HA9 WPort Bdata write
RPort Bdata read
&HAA WPort Cdata write
RPort Cdata read
&HAB WMode set
&H90 WStrobe output (bO) latch output
RStatus input (bl) “1” is
BUSY
&H91 WPrint data latch output
I/O addresses from 80 to FF area prescribed as
above for system use. Empty columns are system
reserves.
*1/0 addresses marked with an asterisk are for
optional equipment.

(2) PPI bit allocation
Port Bit Input/
output Signal Details
A0CSOL Slot designation number of ad-
dresses
1CSOH 0000 to 3FFF
2CS1L Slot designation number of ad-
dresses
3Ou put CS1H 4000 to 7FFF
4CS2L Slot designation number of ad-
dresses
5CS2H 8000 to BFFF
6CS3L Slot designation number of ad-
dresses
7CS3H C000 to FFFF
B0
S
7
Infut Keyboard return signal
C0KBO
2KB2 Keyboard scan signals
3Output KB3
4CASON Cassette control (L-ON)
5CASW Cassette write signal
6CAPS CAPS lamp signal (lights when low)
7SOUND Sound output based on software

(3) PSG bit allocation
Port Bit Input/
output Connector pin no. Signal when
joystick used
A0CONTROLLER 1-1 pin *1 FWD1
CONTROLLER 2-1 pin *2 FWD2
1CONTROLLER- 1-2 pin *1 BACK1
CONTROLLER 2-2 pin *2 BACK2
2CONTROLLER 1-3 pin *1 LEFT1
CONTROLLER 2-3 pin *2 LEFT2
3CONTROLLER 1-4 pin *1 RIGHTI
Input CONTROLLER 2-4 pin *2 RIGHT2
4CONTROLLER 1-6 pin *1 TRGA1
CONTROLLER 2-6 pin *2 TRGA2
5CONTROLLER 1-7 pin »1 TRGB1
6
CONTROLLER 2-7 pin *2 TRGB2
7CASR (cassette tape read)
B 0 CONTROLLER 1-6 pin *3
1
2CONTROLLER 2-6 pin *3 >High level
3Out >ut CONTROLLER 2-7 pin *3
4CONTROLLER 1-8 —
5CONTROLLER 2-8 -
6Port Ainput select
.
*1: Effective when port Bbit 6is low. For CONTROLLER 1
*2: Effective when port Bbit 6is high. For CONTROLLER 2
*3: Set high when the port is not used as an output port.

(4) Expansion I/O registers (slot #2)
LCON register <7FFE (16)>
Bit RW Signal Function
7
RACK Significant with acknowledge 1-»0
with respect to remote control signal
transmission
6
..
1
0
RRMCLOK Clock produced by dividing
CLK1/CLK2 frequency by 128
WREM High output with bit serial data out-
put generated in synchronization with
RMCLK
VCON register <7FFF (16)>
Bit RW Signal Function
7
REXTV Status indicating availability of exter-
nal video signal. Low when available;
high when not available.
WMute Line input signal muting
6
-^====;
|
1
0
R INTEXV Interrupt available with interrupt flag
1when external video signal is OFF.
Set to 0when read.
WOVERLAY Hardware selection signal of superim-
pose/non-superimpose mode; 0for
superimpose, 1for non-superimpose
1.5 CONNECTOR
(1) System control output 1
®vpRVOVLY (OUT)
©-^ yLEXTREMO(OUT)
Stereo mini-jack
(3) System control output 2
®vp©CREMO(OUT)
(?)
—
-U GND
(2) System control input
RSELECT I(IN)
LEXTREMI(IN)
Stereo mini-jack
®vri
©-^ y

(4)
System control output 3
Pin No. Signal I/O
1SELECTO o
2
3
4LACK I
5
6
7LREMO o
8
(5)
RGB connector
Horseshoe-shaped
8-pin DIN connector
Pin No. Signal Logical
porality
1
2GND
3
4Horizontal sync
signal Negative
5Vertical sync
signal Negative
6RED Positive
7GREEN Positive
8BLUE Positive
Round 8-pin DIN connector
(6)
Cassette interface connector
‘INPUT or OUTPUT based on unit.

(7) Keyboard interface connector
Pin No. Signal I/O
1D6 I
2D5 I
3D2 I/O
4D1 I/O
5D7 I
6D3 I
7D4 I/O
8DO I/O
9+5V
10 STB 0
11 GND
12 CAPS 0
13 GND
(8) Printer connector
Pin No. Signal I/O
1PSTB 0
2PDBO o
3PDB1 0
4PDB2 o
5PDB3 o
6PDB4 0
7PDB5 o
8PDB6 o
9PDB7 o
10 NC
11 BUSY I
12 NC
13 NC
14 GND
Round 13-pin connector
Amphenol 14-pin connector