CBM 720 / 720D
(D)
As mentioned on the page for the B128,
the CBM-II models were Commodore's last effort to
capture the business market with it's superior proprietary technology.
All the machines in this line are distinguished by the MOS 6509 processor,
Commodore BASIC 4.0 (like that found in the later
CBM/PET computers, the Commodore "SID" sound chip, IEEE-488 peripheral
compatibility, an RS232-C port, and 80 column text video capability.
Seen here is the CBM 720, the European version of the CBM 256-80 HP
computer. The 720, being a high-
profile model, also includes the ability to attach an optional 8088 or Z-80
coprocessor board, as well as the crisp built in display. A full 256k of banked
memory is also included, which BASIC fully supports for variable storage.
This particular 720,
for some reason, appears to have the beginnings of a pair of IEC (Commodore Serial)
ports worked into it. Check out the "back" view in the ports area below. Also
check out the internal closeup view of the IEC wireing pictured just below
(click on the image for an enlargement).
The 720-D, shown here, is identical to the 720 except for the addition of dual
CBM 8250 compatible mechanisms, with a full meg of
storage capacity on DSDD 5.25" disks.
These two models on this page represent the top of the CBM-II line.
The stylishly curved
plastic case with detachable keyboard and built in monitor are a contrast to the
rest of the CBM-II models, giving them their "High Profile"
distinction.
Statistics, features, and CBM-II machine resources:
CPU |
MOS 6509
2 Mhz
8088 daughterboard inc
|
RAM |
256 kilobytes
Expandable to 704k external
|
ROM |
24 kilobytes
CBM-II Kernal
CBM Basic 4.0
|
Video |
MOS 6545 CTRC
Monitor: 12" Monochrome display
80 columns, 25 rows
|
Sound |
MOS 6581 SID
3 voice stereo synthesizer/digital sound capabilities
|
Ports |
Male edge-connector IEEE-488 port
Male edge-connector CBM Datasette port
Female RS232 port
Female edge-connector CBM-II/PET-II expansion port
1 RCA audio port
Power and reset switches
Two Commodore Serial Ports?!?!
|
Kyboard |
Full-sized 102 key QWERTY
19 key numeric keypad!
4 direction cursor-pad
|