hp75c

Model:	-75C

General:
	Name:			Portable Computer
	Code-Name:		Kangaroo
	Family:			none
	Logic:			Basic
	Features:		basic, clock, appointments
	Firsts:			portable computer
	Introduction:
		Date:		1982-9-15
		Price:		$995
	Discontinuation:
		Date:		1984-05-01
		Price:		$995
	Production-Run:		?

Display:
	Type:			LCD bitmap
	Size:			1 line x 32 chars, 9 x 160 pixels
	Number-Formats:		-
	Annunciators:		BATT	low battery
				ERROR	error condition
				PRGM	running a program
				APPT	appointment due

Data:
	User-Visible:
		Smallest:	1E-499
		Largest:	9.99999999999E499
		Signif.-Digits:	12
	Internal:
		Smallest:	1E-499
		Largest:	9.99999999999E499
		Signif.-Digits:	12
	Data-Types-and-Sizes:	long real (as above) [12 bytes]
				short real +/-9.9999E99 to +/-1E-99 [8 bytes]
				integer +/-99999 [7 bytes]
				one-dimensional numeric array [10 bytes +
					long	8 bytes/element
					short	4 bytes/element
					integer	3 bytes/element]
				string [8 bytes + dimensioned length]
				all arithmetic is done as long real:
				  short real and integer values must
				  be converted to long and back on each
				  operation

				appointments [15 bytes for the file +
					7 bytes/appt +
					1 byte/char in the notes field +
					5 bytes/repeating appt]
				data items [5 bytes/DATA statement +
					2 bytes/item +
					4 bytes/integer +
					9 bytes/real +
					1 bytes/character in strings]
				data pointers [15 bytes/item in ASSIGN#]
				files (BASIC and text) [15 bytes/file +
					3 bytes/line +
					1-3 bytes/keyword(BASIC) or
					1 byte/char of text]
				HP-IL assignments [7 bytes/device]
				key redefinitions [3 bytes/definition +
					1 byte/char + 1 byte for ;]
				mass storage commands [43 bytes/command]
				mass storage devices [105 bytes/device]
				PACK command [256 bytes + 6 bytes/file]
				program CALLs [30 bytes/CALL +
					2 bytes/calling program variable +
					variable storage]
				timers [63 bytes/timer + timer instructions]
				TRANSFORM command [up to 255 bytes]

Memory:
	Named-Registers:	-
	Flags:			-
	Register-Usage:		-
	Numbered-Registers:	-
	Program-Steps:		-
	Program-Editing:	-
	Program-Display:	alpha
	User-RAM-Bytes:		16K
	Total-RAM-Bytes:	24K
	ROM-Bytes:		48K (can grow to 96K)
	Machine-State:		-
	File-Types:		internal: not described
				external: see LIF
Physical:
	Technology-Used:	CMOS
	Processor:		Capricorn, 8-bit (series 80)
	Chip-Count:		21
	Power-Source:		3 nickel-cadmium AA cells, AC
	Continuous-Memory:	yes
	Expansion-Ports:	3 total, can hold:
					32K byte ROM expansions
					(at most 1) 8K byte RAM expansion
	I/O-Ports:		HP-IL
				hand-pulled card reader
				beeper
	Clock:			yes, auto power off

	Length:			12.7 cm
	Width:			25.4 cm
	Height:			3.2 cm
	Weight:			737.1 g
	Temperature-Range:
		Operating:	0 to 45 deg C
		Charging:	10 to 40 deg C
		Storage:	-40 to 55 deg C

Keyboard:
	Switches:		none
	Shift-Keys:		shift, gold, above
				ctrl, not shown
	User-Defined-Keys:	all

Key-Arrangement::

**  **  **  **  **  **  **  **  **  **  **  **
  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***
**  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***
***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***
  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***  ***
                 ***********************

Key-Labels-Base-Keyboard::

ATTN TIME APPT EDIT ^    v    <    >    I/R  FET  DEL  CLR
1    2    3    4    5    6    7    8    9    0    -    +    BACK
CTL  Q    W    E    R    T    Y    U    I    O    P    *    TAB
LOCK A    S    D    F    G    H    J    K    L    ;    =    RTN
SHIFT Z   X    C    V    B    N    M    ,    .    /    SHIFT RUN
[]

(The CTL key is in blue and the SHIFT keys are in gold.)

Key-Labels-Shift-Gold-Above::

[]   []   []   []   []   []   []   []   []   []   []   []
!    "    #    $    %    &    '    (    )    [    ]    @    ESC
[]   []   []   []   []   []   []   []   []   []   []   ^    []
[]   []   []   []   []   []   []   []   []   []   :    []   []
[]   []   []   []   []   []   []   []   <    >    ?    []   []
[]

(The ESC key is in blue.)

Programmable-Operations::

not listed (maybe in a later version)

Non-Programmable-Operations::

not listed (maybe in a later version)

Menus::

none

Bugs/ROM-Versions::

Revision A ROMs:

- CATalog will give a different error message when sent to the display
vs. the printer.

- A "ROM missing" error may lock up the machine (ROM instructions
compiled into program, but ROM not plugged in).

- Large character string dimensions (e.g., >32000) should cause "out
of memory" but instead trashes memory.

- The PRGM annunciator can be on even if the unit is off:

	10 ON TIMER #1, 3 BEEP
	20 OFF TIMER #1
	30 BYE

- Renaming a non-existant file to itself will lock up the unit:

	10 PURGE 'XX'
	20 RENAME 'XX' TO 'XX'

- Setting a variable to null causes its old value to be used for file
commands:

	A$='ABC'
	A$=''
	EDIT A$

causes an edit of file 'ABC'.

- READ # ignores "out of memory".

- The plug in module simulator will lock up if it encounters a MARGIN
command.

- Differences between two successive TIME commands may be negative if
less than one second apart.

- If the time is within one second of midnight, the TIME command may
lock up the unit.

- If you run a program from the keyboard and stop it, all non-program
mode variables are garbage:

	EDIT 'SAMPLE'
	10 FOR I = 1 TO 1000
	20 BEEP
	30 NEXT I
	A = 1
	B = 2
	CALL 'SAMPLE'
	<press ATTN>

A and B are now garbage.

- Data that looks like a number but isn't (e.g., 10 DATA 2.5Y) will
cause it to hang.

- Multiple assignment doesn't work with string variables.

- If the last line number plus the number increment is greater than
9999, RENUMBER will number by ones.

- If memory is almost full, running a program can cause a lock up. 
This is because the "pre-compiler" doesn't pay attention to "out of
memory."

- (Not a bug) The hex digits used by ADJUST and ADJUST$ are reversed
compared to regular numbers.

- Applications of EXACT after the first one may cause it to become
less exact.

- The quarter-second time adjustments may case something to be sent
around the loop, thus waking up devices in standby mode.

Notes::

The pre-release product numbers were -75C 8K of memory and -75D 16K of
memory.  The -75C apparently came out with 16K of memory.  This is
still confusing.

The source listing for this machine is (was) available.  Much of the
documentation was in the form of dialogue between the characters
"Roo-man" (the expert) and "Joey" (the novice).

Cards hold 1.3K bytes each.  The same cards -- but not data formats --
are used with the -71B.

An expansion pod is available.  This pod wraps around the -75* and
contains a direct-connect 300 bps modem, either 32K or 64K bytes of
additional memory (depending upon the option), and bar code reading
software (for the -75D).  The pod plugs in through the rightmost
expansion port.  The additional memory shows up like an electronic
disk (can't be used for variable storage or scratch memory and you
can't run a program directly from it).  On the other hand, you can
create directories (separator characer is ">").