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- As promised earlier, here's the first installment of info on Apple's LISA
- workstation. Each installment will contain stuff from the LISA spec sheets
- which I received at the Philly OAC, as well as comments and pointers where
- appropriate. I'll also place all of these summaries in one of the MC;CPM
- archives.
-
- ------------------------------
-
- Hardware Specifications: Apple LISA
-
- Display: 12 inch (diagonal) screen
- Bit mapped display: 720 x 364
- Up to 45 lines of 144 characters
- <comment: these are VERY small chars; chars will usually be larger>
- 60 Hz refresh rate
-
- Keyboard: Detached, N-key rollover, sculptured keycaps
- Full ASCII Character set
- <comment: no "CONTROL" key, command key may be used as such for
- terminal emulation>
- Numeric Keypad
- All keys are programmable
- <comment: keyboard under control of NS COPS processor>
-
- Mouse: Optomechanical, using small "trackball" and shaft encoders
- One button
- <comment: One button was selected to elimiate confusion>
- <comment: Small Trackball may be removed for cleaning>
-
- Main Processor: MC68000
- CPU running at 5 MHz
- <comment: 5 MHz operation required because video controller cycle
- steals memory from the CPU to provide streakless display>
-
- Main Memory: 1 Megabyte RAM, with parity checking
- 16K bytes of boot ROM
- <comment: Operating System locks out bad blocks of RAM>
-
- Disk storage: Two 5 1/4" floppy disk drives, 860K each
- <comment: Drives are VERY non-standard, and use CLV
- for constant density>
- ProFile 5 Mb hard disk
- <comment: ProFile contained in seperate cabinet>
- Automatic disk eject and head loading under software control
- Uses MOS6504 as controller
-
- Memory Management: Segmentation into 128 variable length blocks
- dynamically controlled through memory map table
- Operating System may relocate segments in memory
- Provides access controls for blocks of memory
-
- Comm I/O: Two serial I/O ports
- Supports async, bisync, SDLC, and HDLC
- RS-232, half or full duplex, with full modem control on one port
- Baud rate and other attributes under software control
-
- One parallel Port, MOS6522 I/O chip
- 8 bit bidirectional port with handshake signals
-
- Real Time Clock: Interval and event timing
- Time of Day Clock
- Software on-off control
- Battery Backup
-
- Audio Output: Built-in Speaker with software controllable oscillator
-
- Expansion board slots: Three slots, ZIF connectors
- Access to system bus
- DMA, Memory Mapped I/O, and Vectored Interrupts
- +5 V, -5 V, +12 V, and -12 V provided
-
- Weight and Physical Dimensions:
-
- Main Unit: Weight: 48 lbs (22 kg)
- Height: 13.8 inches (350 mm)
- Width: 18.7 inches (475 mm)
- Depth: 15.2 inches (388 mm)
-
- Keyboard: Weight: 4 lbs (1.8 kg)
- Height: 2.7 inches (68 mm)
- Width: 18.7 inches (475 mm)
- Depth: 6.5 inches (165 mm)
-
- <comment: Main unit with keyboard under front has depth of 16 inches (403 mm)>
-
- Power Requirements: 115 or 230 VAC
- 48 to 68 Hz
- 270 Watts Maximum
-
- Environmental Requirements: Ambient Operating Temp: 40F-108F (5C-42C)
- Relative Humidity: 15-80% noncondensing
-
- <comment: Main unit is convection cooled, no fan>
-
- ----------
-
- Additional Comments and Observations:
-
- From a servicing standpoint, the LISA is a dream. The whole unit,
- except for the monitor, is modular and snaps apart, including the
- drives. So, for ultimate realiablity, one could keep spare boards and
- drives on hand. The diagnostics are quite extensive, and can determine
- specific faults under most circumstances.
-
- The CRT has a non glare shield on it, and the picture is very sharp.
- Brightness and contrast are software controllable.
-
- While the LISA has alot of memory and uses a 68000, the hardware specs
- are acceptable, but by no means revolutionary (or even special).
- Apple claims that the "Twiggy" floppy drives have a very low error rate.
- I guess this was a problem in 1980, when the LISA was being designed, but
- what they wound up with is a drive not significantly more reliable than a
- Tandon DDDS 5 1/4" floppy, but COMPLETELY non-standard. One of the
- problems with the old double sided drives was excessive media wear from
- both heads touching the diskette at about the same place. Drive
- manufacturers performed "Tap Tests" to see how many head loads and unloads
- were required before the diskettes and/or heads gave out. Apple's
- solution to this problem was to put the top and bottom heads on opposite
- sides of the diskette. So, what you have is a 5 1/4" diskette with two
- slots for heads, one in the normal place, and the other where the label
- normally goes. Other companies, such as Tandon, solved the problem by
- always having the heads loaded. It turns out that this is much easier
- on both the heads and the diskettes, and removes the need for a head
- load solenoid. Thanks to Apple, we now have a new (yeech!) media
- type, not to mention format, because they use CLV rather than CAV, to
- keep density constant. I'm sure the magnetic media manufacturers are
- overjoyed.
-
- The ProFile hard disk is not exactly what I'd call state-of-the-art...
- as a matter of fact, it is pretty slow. The fact that the hard disk
- is in a seperate box is another problem, because now you have to put
- it somewhere. In summary the LISA would be even nicer if it had one
- Thin-Line DDDS Drive and one SyQuest Removable Hard Disk.
-
- What I'm getting at is that the LISA is not amazing from a hardware
- standpoint. Rather, it is the software which makes this machine so
- flexible and powerful. We'll be looking at the LISA applications
- programs in the next installment of this newsletter.
-
- Dan