TANDY/RADIO SHACK
4820ST/T (250-5140)
|
Processor |
80486SX/80487SX/ODP486/ODPR486/80486DX/80486DX2 |
|
Processor Speed |
20/25/33/40/50(internal)/50/66(internal)MHz |
|
Chip Set |
Unidentified |
|
Video Chip Set |
None |
|
Maximum Onboard Memory |
64MB |
|
Maximum Video Memory |
None |
|
Cache |
None |
|
BIOS |
Unidentified |
|
Dimensions |
330mm x 218mm |
|
I/O Options |
Floppy drive interface, IDE interface, parallel port, PS/2 mouse port, serial ports (2) |
|
NPU Options |
80487SX |
|
CONNECTIONS | |||
|
Purpose |
Location |
Purpose |
Location |
|
PS/2 mouse port |
CN1 |
IDE interface |
CN6 |
|
Serial port 1 |
CN2 |
Power indicator |
J1 |
|
Serial port 2 |
CN3 |
IDE interface LED |
J2 |
|
Parallel port |
CN4 |
External battery |
J3 |
|
Floppy drive interface |
CN5 |
Front panel connector |
J4 |
|
USER CONFIGURABLE SETTINGS | |||
|
Function |
Label |
Position | |
|
» |
CMOS memory normal operation |
JP1 |
Open |
|
CMOS memory clear |
JP1 |
Closed | |
|
» |
Monitor type select color |
SW1/3 |
On |
|
Monitor type select monochrome |
SW1/3 |
Off | |
|
» |
Factory configured - do not alter |
SW1/4 |
Unidentified |
|
DRAM CONFIGURATION | ||||
|
Size |
Bank 0 |
Bank 1 |
Bank 2 |
Bank 3 |
|
1MB |
(4) 256K x 9 |
None |
None |
None |
|
2MB |
(4) 256K x 9 |
(4) 256K x 9 |
None |
None |
|
3MB |
(4) 256K x 9 |
(4) 256K x 9 |
(4) 256K x 9 |
None |
|
4MB |
(4) 256K x 9 |
(4) 256K x 9 |
(4) 256K x 9 |
(4) 256K x 9 |
|
4MB |
(4) 1M x 9 |
None |
None |
None |
|
5MB |
(4) 256K x 9 |
(4) 1M x 9 |
None |
None |
|
6MB |
(4) 256K x 9 |
(4) 256K x 9 |
(4) 1M x 9 |
None |
|
8MB |
(4) 1M x 9 |
(4) 1M x 9 |
None |
None |
|
9MB |
(4) 1M x 9 |
(4) 1M x 9 |
(4) 256K x 9 |
None |
|
10MB |
(4) 256K x 9 |
(4) 256K x 9 |
(4) 1M x 9 |
(4) 1M x 9 |
|
12MB |
(4) 1M x 9 |
(4) 1M x 9 |
(4) 1M x 9 |
None |
|
16MB |
(4) 1M x 9 |
(4) 1M x 9 |
(4) 1M x 9 |
(4) 1M x 9 |
|
16MB |
(4) 4M x 9 |
None |
None |
None |
|
17MB |
(4) 256K x 9 |
(4) 4M x 9 |
None |
None |
|
18MB |
(4) 256K x 9 |
(4) 256K x 9 |
(4) 4M x 9 |
None |
|
20MB |
(4) 1M x 9 |
(4) 4M x 9 |
None |
None |
|
24MB |
(4) 1M x 9 |
(4) 1M x 9 |
(4) 4M x 9 |
None |
|
32MB |
(4) 4M x 9 |
(4) 4M x 9 |
None |
None |
|
33MB |
(4) 4M x 9 |
(4) 4M x 9 |
(4) 256K x 9 |
None |
|
34MB |
(4) 256K x 9 |
(4) 256K x 9 |
(4) 4M x 9 |
(4) 4M x 9 |
|
36MB |
(4) 4M x 9 |
(4) 4M x 9 |
(4) 1M x 9 |
None |
|
40MB |
(4) 1M x 9 |
(4) 1M x 9 |
(4) 4M x 9 |
(4) 4M x 9 |
|
48MB |
(4) 4M x 9 |
(4) 4M x 9 |
(4) 4M x 9 |
None |
|
64MB |
(4) 4M x 9 |
(4) 4M x 9 |
(4) 4M x 9 |
(4) 4M x 9 |
|
CPU TYPE SELECTION | |||
|
Type |
Socket |
SW1/1 |
SW1/2 |
|
80486SX |
CPU |
Off |
Off |
|
ODP486 |
CPU |
On |
On |
|
ODP486 |
NPU |
Off |
Off |
|
ODPR486 |
CPU |
On |
Off |
|
80487SX |
CPU |
On |
On |
|
80487SX |
NPU |
Off |
Off |
|
80486DX |
CPU |
On |
Off |
|
80486DX2 |
CPU |
On |
Off |