Panasonic JR-200
| Panasonic JR-200U, from Panasonic's operating instructions | |
| Specifications | |
|---|---|
| Manufacturer | Matsushita (National and Panasonic brands) |
| Type | Home computer |
| Released | Late 1982 (Japan, as the National JR-200); announced January 1983 (JR-200U, North America and Europe)[1][2] |
| Intro price | ¥79,800 (Japan)[1] |
| CPU | Matsushita MN1800A (6802 equivalent); MN1544CJR keyboard sub-CPU[3] |
| Memory | 32 KB RAM, 2 KB video RAM, 2 KB character RAM |
| Storage | Cassette, 600 or 2400 baud |
| Display | 32 × 24 characters, 8 colours; 64 × 48 block graphics |
| Sound | Three-note melody over five octaves; internal speaker |
| ROM | 16 KB (JR-BASIC 5.0) |
| Ports / interface | RGB/composite video (DIN), RF, cassette (DIN), Centronics printer, two joystick ports, external bus, external speaker |
| Power | 120 V AC ±10 %, 50/60 Hz, 8 W maximum (JR-200U); 100 V AC, about 8 W (Japan) |
| Dimensions | 348 × 208 × 56 mm |
| Weight | About 2.3 kg (JR-200U service manual); 1.7 kg or 2.0 kg (Japanese sources) |
| OS / Firmware | — |
| Predecessor | Panasonic JR-100 |
| Model no. | JR-200, JR-200U, JR-200UP |
The Panasonic JR-200 is an 8-bit home computer made by Matsushita. It went on sale in Japan at the end of 1982 as the National JR-200, priced at ¥79,800. It replaced the JR-100 but cannot run its software.[1] The export version, the Panasonic JR-200U, was announced for North America and Europe in January 1983, and a PAL version was sold as the JR-200UP.[2] The power supply is built into the case.[3]
Specifications
[edit | edit source]| Item | Panasonic's figure |
|---|---|
| CPU | MN1800A (equivalent to 6802) |
| Memory | 16 KB ROM (BASIC), 32 KB RAM, 2 KB video RAM, 2 KB character RAM |
| Keyboard | 63 keys, read by a sub-CPU |
| Display | RGB with separate sync, composite video, RF on channel 3 or 4; 24 lines of 32 characters in 8 colours; 64 × 48 graphics |
| Characters | 95 alphanumeric, 64 graphic symbols, 17 other symbols, 64 user-defined |
| Music | Five octaves, three-note chords |
| Interfaces | Cassette at 600 or 2400 baud; Centronics printer; two joystick sockets |
| Language | JR-BASIC 5.0 and machine language |
| Power | 120 V AC ±10 %, 50/60 Hz, 8 W maximum |
| Size and weight | 348 × 208 × 56 mm; about 2.3 kg (5-1/16 lb) |
[3] The cover of the service manual misprints the labels on the dimensions; the Japanese figures give 56 mm as the height, 348 mm as the width and 208 mm as the depth.[3][1]
Hardware
[edit | edit source]| Ref | Part | Function |
|---|---|---|
| IC1 | HD61K201F | CRT controller |
| IC2 | MN1800A | Main CPU |
| IC4, IC5 | MN4864CA2, MN4864CB2 | 8 KB ROMs (ROM 0, ROM 1) |
| IC6 | HM6116P3 | Character RAM (2 KB) |
| IC7 | HM6116P3 | Video RAM (2 KB) |
| IC8 to IC11 | HM4864P3 | Dynamic RAM, 64 K × 1 bit each (32 KB) |
| IC17 | MN1271 | I/O controller (PIA) |
| IC18 | MN1544CJR | Keyboard and joystick sub-CPU |
| IC34 | YLHSI8053B | +5 V regulator |
[3] The display timing on NTSC machines comes from a 14.31818 MHz crystal.[3] Figures for the CPU clock differ. Wikipedia gives 0.89 MHz as unconfirmed. Markku Reunanen points out that 0.89 MHz is the NTSC colour carrier divided by four, estimates about 1.366 MHz from code timing, and reports that the service manual gives 1.34 MHz for NTSC machines; PAL machines use a different crystal.[2][4] The sound comes from timers in the MN1271, not from a separate sound chip.[4] The service manual's troubleshooting chart for missing sound also leads to the PIA, IC17.[3]
Power supply
[edit | edit source]The mains passes through the power switch SW2 and a line noise filter to the transformer. Its secondary is fused at 1.0 A (F1, 125 V) and rectified by the bridge DB1. After a second filter and a 470 µF reservoir (C38), the regulator IC34 makes the single +5 V rail, smoothed by the choke L2 and a 1000 µF capacitor (C37).[3]
Controls and connections
[edit | edit source]At the rear are the receptacle for the mains lead, the cassette interface, the expansion slot for the optional RS-232C card, the external bus connector, the Centronics printer port, an external speaker socket (8 Ω) with the audio volume knob, the RGB/composite video DIN socket and the RF output. The power switch, power indicator and break key are on the top at the right.[5] The two joystick ports are 9-pin D connectors on the left side, wired like MSX joystick ports.[2][4] The RF channel switch and the colour/monochrome switch are underneath; a transfer speed switch selects 600 or 2400 baud for the cassette.[5]
Known faults
[edit | edit source]Panasonic's service manual has twelve troubleshooting flowcharts, and a RAM test and a ROM test that report the failing chip by its IC number. They are summarised on the Panasonic JR-200 Troubleshooting Guide.[3]
Documentation
[edit | edit source]- Panasonic JR-200 Documentation: the JR-200U service manual (EDCD 83-001) and operating instructions.
Related pages
[edit | edit source]- Panasonic JR-200 General Maintenance
- Panasonic JR-200 Troubleshooting Guide
- Panasonic JR-200 Capacitor Replacement Guide
- Panasonic JR-100
References
[edit | edit source]- ↑ 1.0 1.1 1.2 1.3 JR (コンピュータ), Japanese Wikipedia—link(accessed 2026-10-01) Section "JR-200", citing ASCII December 1982, p. 78. Used for the Japanese launch, price, power rating, dimensions and weight.
- ↑ 2.0 2.1 2.2 2.3 Panasonic JR-200, Wikipedia—link(accessed 2026-10-01) Used for the JR-200U announcement and the PAL JR-200UP.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 Matsushita Engineering and Service Company, Service Manual: Personal Computer JR-200U, order no. EDCD 83-001: specifications (cover), diagnostic programs pp. 1–16, LSI pin configurations pp. 64–71, disassembly p. 73, troubleshooting pp. 75–78, replacement parts list. Hosted here as File:Panasonic JR-200U Service Manual EDCD 83-001.pdf; see Panasonic JR-200 Documentation.
- ↑ 4.0 4.1 4.2 Markku Reunanen, Discovering the Panasonic JR-200U—link(accessed 2026-10-01) Programming and hardware notes: CPU clock, system chips, sound from the MN1271 timers, joystick and expansion port.
- ↑ 5.0 5.1 Matsushita Electric Industrial Co., Operating Instructions: Personal Computer JR-200U: "Important Don'ts" p. 3, "Parts Name" p. 5, specifications p. 47, troubleshooting p. 49. Hosted here as File:Panasonic JR-200U Operating Instructions.pdf.