during development of my NC200 emulation for M.E.S.S.
This update does not cover the NC150. I do not have details of any differencesbetween this and the NC100 at this time.
When I have information on this system, it will be documented here.
of I/O read/writes.
* The NC200 does not have a TC8521 Real Time Clock, instead ithas a MC146818 Real Time Clock. The MC146818 is no longer produced now,but is part of many PC designs.
* The NC200 has a [[NEC765 ]] compatible floppy disc controller. The discinterface was designed by Ranger Computers.
The ports listed in this section are different or have additional
* The NC100 clock speed is 4.606Mhz606MHz, at this time it is unknown if the NC200has a different clock speed.
* The NC100 on/off button generates an NMI.
B5:
bit 0: B?? bit 1: V?? bit 2: TB bit 3: YV bit 4: GT bit 5: Y bit 6: G bit 7: C
B6:
bit 5: L
bit 6: O
bit 7: STOP.
Address Comment R/W
======= ======= ===
00 Display Memory start W
20 Memory card wait state W
bit 7: memory card wait state control: 1 for wait states, 0 for no wait
bit 2: ??
bit 1: ??
bit 0: NEC765 Terminal Count input (1=TC active, 0=TC inactive)
Address = 30 Write only
Floppy motor control
bit 3: Floppy motor: 1=off, 0=on
Address = 70
bit 2: Backlight: 1=off, 0=on
bit 1: ??
bit 0: on/off control: 1 = on, 0 = off
Address = 80
centronics status
bit 0: busy state
Address = A0
[[NC100 IO Specification]]
[[Category:NC Series]]