TANDY/RADIO SHACK
MFP/420s
Processor |
80486SX/80487SX |
Processor Speed |
20MHz |
Chip Set |
Tandy |
Max. Onboard DRAM |
32MB |
Cache |
None |
BIOS |
Phoenix/Grid |
Dimensions |
355mm x 304mm |
I/O Options |
Bus mouse port, floppy drive interface, IDE interface parallel port, serial port (2), VGA feature connector, VGA port |
NPU Options |
4167 |
VRAM CONFIGURATION | |||
Size |
VRAM |
Location |
SW1/switch 6 |
512KB |
(2) 44256 |
Bank 0 |
closed |
1024KB |
(2) 44256 |
Banks 0 & 1 |
open |
CONNECTIONS | |||
Purpose |
Location |
Purpose |
Location |
External battery |
BAT |
Floppy drive interface |
C6 |
Board LED |
BLED |
IDE interface |
C7 |
VGA port |
C1 |
Power LED |
PLED |
Bus mouse port |
C2 |
Reset switch |
RES |
Parallel port |
C3 |
Speaker |
SPK |
Serial port 2 |
C4 |
Riser card |
S1 |
Serial port 1 |
C5 |
USER CONFIGURABLE SETTINGS | |||
Function |
Switch |
Position | |
» |
On-board Video System enabled |
SW1/switch 7 SW1/switch 8 |
closed open |
On-board Video System disabled |
SW1/switch 7 SW1/switch 8 |
open closed | |
» |
Factory configured - do not alter |
SW2/switch 1 |
open |
» |
Factory configured - do not alter |
SW2/switch 2 |
open |
» |
Monitor type select color |
SW2/switch 3 |
open |
Monitor type select monochrome |
SW2/switch 3 |
closed | |
» |
Factory configured - do not alter |
SW2/switch 4 |
open |
VIDEO SWITCH CONFIGURATION (SW1) | |||||
Mode |
switch 1 |
switch 2 |
switch 3 |
switch 4 |
switch 5 |
56Hz vertical refresh 1 |
open |
open |
N/A |
N/A |
N/A |
60Hz vertical refresh 1 |
open |
closed |
N/A |
N/A |
N/A |
72Hz vertical refresh 1 |
closed |
open |
N/A |
N/A |
N/A |
Enable interlaced 2 |
N/A |
N/A |
open |
open |
N/A |
60Hz non-interlaced 2 |
N/A |
N/A |
open |
closed |
N/A |
72Hz non-interlaced 2 |
N/A |
N/A |
closed |
open |
N/A |
31.5KHz horizontal scan rate 3 |
N/A |
N/A |
N/A |
N/A |
open |
40KHz horizontal scan rate 3 |
N/A |
N/A |
N/A |
N/A |
closed |
Note 1 :When monitor resolution is 800 x 600.Note 2 :When monitor resolution is 1024 x 768.Note 3 :When monitor resolution is 640 x 480 or below. |
DRAM CONFIGURATION | ||
Size |
Bank 0 |
Bank 1 |
4MB |
(4) 1M x 9 |
NONE |
5MB |
(4) 1M x 9 |
(4) 256K x 9 |
8MB |
(4) 1M x 9 |
(4) 1M x 9 |
16MB |
(4) 4M x 9 |
NONE |
17MB |
(4) 256K x 9 |
(4) 4M x 9 |
20MB |
(4) 1M x 9 |
(4) 4M x 9 |
32MB |
(4) 4M x 9 |
(4) 4M x 9 |