All who has and with the nostalgia had remembered this calculator can remind how much is this the revolutionary device:
40 Hours of work with the one filling of batteries
300 baud transfer programs and data on the cassette deck
10 way slower from ZX Spectrum
beside the supplement of original data plotters (+cmt the interface) has been able rule the result on 60mm bands
The persistent work and disassembling the system memory beside the usage of original manual gets:
with 4MHz the oscillator acceleration 150 %
the predefined usage keyboards and added HR signs (+Greek and other useful signs)
integration 128K RAMs gets 28k the RAM for BASIC, 2 * 32K RAM of disc, 2 * 16K for system programs
alteration of protocol for the cassette deck, acceleration communications overall 4,2 times (approximately 1200 bauds)
the optocoupler interface for PC (for the purpose of savings of programs)
programmed compiler assebmer the instruction (who interprets as the Basic) in free 3,2K system memory.
programmed the additional Basic commands (the multiplication fields 100 times faster, multyple programm organization, etc.)
work with more Basic programs in the memory of the this simple possibility editings of the once BASIC block
.... and in the end yet stays freely 21K for the system programme
Implementing algorithms have been made:
speeds up the furier transformation FFT
frequency meter (50-16000Hz) on CMT entrance / is digitized osciloscope display of entrance
DC of analyses of nets (methods of loops - elements are resistors, voltage sources,..)
AC of analyses of nets (similar at some time past has been sold by Viktor Kesler). This version uses speeds up matrix multiplications, resized fields in the memory and secondly - elements to the loop is R, L, C, Voltage sources, Dependent voltage amplifiers with amplitude and phase characteristic which can the set by function,...
program for the organization and compile new BASIC instruction this their activation.
program for the execution assembler the instruction step by step (even and along the system ROM)
program for the interruption of the any assembler program (even and in the closed loop)
program for the saving and loading from RAM of disc (2 * 32K)
If has interested who has wanted, but never do not succeed make some similarly freely excange experiences (although is good the part already are forgotten). Majorities of important things has been written down. Otherwise, whole mind steps on one additional cards (free slot) who costs around 400 HRK. Are added the programmatical memory has been supported the battery (because is in RAM). Lack of complex is the possibility of system failure because of empty batteries for the backup. System then was able not will rise typing in 1K the simple Basic of loaders this with the help optocoupler PC of interface read for the hour times mashine program (2K) for the work with the cassette deck. After this loaded the rest of the additional system routines (in a few minutes).
All schemes (memory expansions, CMT of interface) and program for DOS (the preparing and loading the program from age-old PCs instead of with the cassette) was able free of charge to get on request (schemes cost how and copying and postages).
List of the added to Basic to the order and function (own programs)
Block commands for the multyple programm structure (definite necessary when have 28K programmatical memory)
CLM - command - wipes last BASIC block from the programmatical memory
SEM - command - opens new BASIC block in the programmatical memoryi (merge the block)
MOV - command - copies are searched for programmatical BASIC block on the last position
LML - command - list of the last programmatical block
CSV - command - prepares one or more programmatical blocks back-to-back on CMT
Commands which accelerate the work with fields (the 100 way)
CLD - command - cancels dimensioning determining variables
COPY - command - copies fields in fields (the 300 way faster than BASIC commands)
SOUND - command - adds two fields
SUB - command - subtract two fields
MULT - command - multiplies the field with the field
MULF - command - multiplies the field with the coefficient
MULES - command - multiplies the field with the field and adds him
MULS - command - multiplies the field with the field and subtract him
Commands for the assignment function which can will change (without the change of program)
KOD$ - function - code string in string with the Basic code (encodes the Basic commands)
EXEC - command - executes function written down in the string e.g. EXEC A="SIN(B)"
EXEK - command - executes LET command in the string e.g. EXEK "A=SIN(B) "
Commands for the simplification programming at the input and branchings
CODE - function - keyboard the input one character with waiting on the input
CASE - function - serial comparator gives number who answers first full comparisons
CHANGE - command - input which offers the value variables on the exchange
DPEEK - function - word PEEK
DPOKE - command - word POKE
OSC - command - digital one bit display CMT of input
DISP - command - software the turn on and switching off display
BREAK - command - disables the break
CUP - function - display position of graphic cursors
SOUND - command - the parametric howling siren
SCREEN - command - saves or returns graphically the content of screen in free RAM (for fast animations)
HEX$ - function - transformation in the hexadecimalni number
DEK - function - reversely from HEX
ASM - command - command which defined the start and end the assembling
All quoted commands occupy only 6,8K. Only with this additional commands have the true comfort in the programming. The integrated assembler makes possible the assembling directly in RAM (between the program and variable), and most importantly is that assembler commands easily can will change (add and wipe). Testing assembler routine was able wrap with the setting up of deadlocks from who get out the usage of own program BREAK-INT. BREAK-INT makes possible the review of states of registers in the moment of interruptions of program.
More data about PC-1500A can find on the page http://www.pc1500.com
. Here can find and PC emulators of the different SHARP pocket computera also programs for the saving and loading with PCs (across sound cards)