Epson 20 - Manual (Page 190)

Option slots Nine input/output expansion slots; three with
B-bit bus and six with 16-bit bus; one slot
occupied by the serial/parallel/floppy disk
controller card, another occupied by a hard
disk controller card if installed
Speaker
Clock/calendar
RAM
Internal, with volume control
Real-time clock, calendar, and 104-byte
CMOS RAM for configuration; battery
backup
--
Power Supply Switching type, fan-cooled, 115/230 VAC,
190 W; +5 VDC, +12 VDC, -5 VDC,
- 12 VDC; 50/60 Hz
Mass Storage
Four drives maximum, configurable using
three 5¼-inch half-height drives and one
5¼-inch full-height drive
Standard
Optional
Optional
Optional
Optional
Optional
Optional
5¼-inch, half-height floppy disk drive; 1.2MB
(high-density) storage capacity
5¼-inch, half-height floppy disk drive; 1.2MB
(high-density) storage capacity
5¼-inch, half-height floppy disk drive; 360KB
(double-density) storage capacity
3½-inch, half-height floppy disk drive; 720KB
(double-density) storage capacity
3½-inch, half-height floppy disk drive;
1.44MB (high-density) storage capacity
5¼-inch, half-height hard disk drive; 40MB
storage capacity
5¼-inch, half-height hard disk drive; 90MB
storage capacity
F-2 Specifications