This section provide essential information for using ROM functions

LCD Function

Funciton Name	Description	Entry condition	Exit condition	Entry Address (Hex.)
LCD	Displays a character on the LCD at current cursor position (Also RST 4)	A= Character to be displayed	none	4B44
SETCUR	Move cursor to specified location.	D = column number ( 1-40 ) E = row number	none	7440
PLOT	Turn on pixecl at specified location.	D= x coordinate (0-239) E = y coordinate (0-63)	none	744C
UNPLOT	Turn off pixecl at specified location	D = x coordinate (0-239) E = y coordinate (0-63)	none	744D
POSIT	Set cursor position.	H = column number (1-40) L = Low Number	none	427C
ESCA	Send Specified Escape Code Sequence	A = escape code	none	4270

Routines for Generating Common LCD Functions and Escape code

Function Name	Description	Entry Address (Hex.)	Equiv. ESC
CRLF	Generate a Carriage Return and Line Feed	4222	--
HOME	Move cursot to Home position (1,1)	422D	--
CLS	Clear display	4231	--
SETSYS	Set system Line (lock line 8, Label)	4235	T
RSTSYS	Reset system line (unlock line 8, Label	423A	U
LOCK	Lock Display (no scrolling)	423F	Y
UNLOCK	Unlock display (scrolling)	4244	W
CURSON	Turn on cursor	4249	P
CUROFF	Turn off cursor	424E	Q
DELLIN	Delete line at cursor position	4253	M
INSLIN	Insert a blank line at cursor position	4258	L
ERAEOL	Erase from cursor to end of line	425D	K
ENTREV	Set Reverse chracter mode	4269	P
EXREV	Turn off Reverse character mode	426E	q

Variable and Status Locations

Name	Contents	Address
CSRY	Cursor Position (ROW)	F639
CSRX	Cursor Position (Column)	F63A
BEGLCD	Start of LCD memory	FE00
ENDLCD	End of LCD memory	FF40

Keyboard Functions

Function Name	Description	Entry Conditions	Exit conditions	Entry Address (Hex)
KEYREAD	Scan keyboard for a key. Return with or without one.	none	A = character, if any Flag Set Reset Z No key found Key found Carry Character in code table below Normal character set code When Carry is set, Register A will contain one of the following: Register A value Key Pressed 0 F1 1 F2 2 F3 3 F4 4 F5 5 F6 6 F7 7 F8 8 LABEL 9 PRINT 0A Shift-PRINT 0B PASTE	7242
CHGET	Wait and get character from Keyboard	none	A = character code Carry --set if special character Carry --reset if normal character (<F1>-<F8> return preprogrrammed strings)	12CB
CHSNS	Check keyboard queue for characters	none	Z flag set if queue empty, rest if keys pending	13DB
KEYX	Check keyboard queue for chracters or BREAK	none	Z flag set if queue empty, reset if keys pending Carry flag set when BREAK entered, reset with any other key	7270
BRKCHK	Check for BREAK characters only (CTRL-C or -S)	none	Carry flat is set if BREAK or PAUSE entered, reset if not BREAK characters	7283
INLIN	Get line from keyboard (terminated by <ENTER>)	none	Data stored at location F685	4644

Using Function Keys Routines

The function table consists of character strings to be used by the keyboard driver when processing <F1> - <F8> keys. The strings have maximum length of 16 characters and are terminated by a "80" ( Hex.) code. If the last character of the string is OR'ed with 80, the character will also serve as a terminator. The entire string will be placed in the keyboard buffer when the appropriate strings for all 8 key is pressed. You must specify character strings for all 8 function keys (use the terminator byte for any you wish to ignore).

Example of Function table

    FCTAB   DEFM 'Files'    ; F1
            DEFW  0D80
            DEFM 'Load'     ; F2
            DEFB 80
            DEFM 'Save'     ; F3
            DEFB 80
            DEFM 'Run'      ; F4
            DEFW 0D80
            DEFM 'List'     ; F5
            DEFW 0D80
            DEFB 80         ; Ignore F6
            DEFB 80         ; Ignore F7
            DEFM 'Menu'     ; F8
            DEFW 0D80

Function Name	Description	Entry onditions	Exit conditions	Entry Address (HEX)
STFNK	Set Function key definitions	HL = Address of function table (above)	none	5A7C
CLRFLK	Clear function key definition table (fills with 80's)	none	none	5A79
DSPNFK	Display function keys	none	none	42A8
STDSPF	Set and display function keys	HL = Start address of function table	none	42A5
ERAFNK	Erase function key display	none	none	428A
FNKSB	Display function table (if enabled	none	none	5A9E

Printing Routines

Function Name	Description	Entry conditions	Exit conditions	Entry Address (Hex)
PRINTR	Send a character tothe line printer	A = Character to be printed	Carry is set if cancelled by BREAK, reset if normal return	6D3F
PNOTAB	Print character without exanding tab characters	A = character to be printed		1470
PRTTAB	Print a character expandign tabs to spaces	A = character to be printed		4B55
PRTLCD	Print contents of LCD	none	none	1E5E

RS232-C and Modem Routines

Function Name	Description	Entry conditions	Exit conditions	Entry address (Hex)
DISC	Disconnect Phone line	none	none	52BB
CONN	Connect phone line	none	none	52D0
DIAL	Dial a specified phone number	HL = Ph. number address	none	532D
RCVX	Check RS232 queue for characters	none	A = number of characters in queue Z flas is set if no data, reset if characters pending	6D6D
RV232C	Get a character from Rs232 received queue	none	A = character received Z flag set if O.K., reset if error (PE, FF, or OF) Carry set if Break pressed, else reset
SENSCQ	Send an XON resume character (CTL-Q)	none	none	6E0B
SENDCS	Send an XOFF pause character (CTL-S)	none	none	6E1E
SD232C	Send a character to the RS-232 or Modem (with XON/XOFF)	A = character to be sent		6E32
CARDET	Detect carrier	none	A = 0 if carrier Z flag is set if carrier, else reset	6EEF
SNDCOM	Send a character to RS232-C or modem (wihtout XON?XOFF flow control)	C = characer to be sent		6E3A
BAUDST	Set Baud rate for RS232-C	H = Baud rate (1-9,M)	none	6E75
INZCOM	Initiailize RS232-C and Modem	H = Baud rate (1-9,M) L = UART configuratin code (see UART byte description below) Bit 0: specifies number of Stop Bits 0=1, 1=2 Bit 1-2: Parity Setting. 00=None, 01 = Even, 10 = Odd Bit 3-4: Word Length: 00=6, 01=7, 10=8 The byte is ANDed wit 1FH to ignore Bits 5-7. The text string containign hte current STAT settings is located at F65BH(5 bytes): Baud, Length, Parity, Stop Bits and XON/XOFF switch.	none	6EA6
SETSER	Set serial interface parameters and acivate RS232-C/Modem	HL = Start address of ASCII string containing parameters terminated by a binary zero ('78E1E',0). Syntax same as in Telcom's STAT Carry set for RS232-C, reset for Modem	none	17E6
CLSCOM	Deactivate RS232-C/Modem	none	none	6ECB

Cassette Recorder Routines

Function Name	Description	Entry Conditions	Exit Conditions	Entry Address (HEX)
DATAR	Read character from cassette (no checksum)	none	D = character from cassette	702A
CTON	Turn motor on	none	none	14A8
CTOFF	Turn motor off	none	none	14AA
CASIN	Read a character from cassette and update checksum	C = current checksum	A = character C = contains the updated checksum	14B0
CSOUT	Send character to cassette and update checksum	A = character to be sent C = current checksum	C = updated checksum	14C1
SYNCW	Write cassette header and sync byte only	none	none	6F46
SYNCR	Read cassette header and sync byte only	none	none	6F85
DATAW	Write a character to cassette (no checksum)	A = character to be sent	none	6F5B

RAM Files Routines

The Directory Table (located at F962) contains all file location, type and status information.

Each file is managed by an 11-byte directory entry in the format:

        Byte 1: Directory Flag (for file type and status)
        Bytes 2-3: Address of file
        Bytes 4-11: 8 Byte filename
    

The Directory Flag contains the following information:

        Bit 7 MSB   1 if a valid entry
        Bit 6       1 for ASCII text file (DO)
        Bit 5       1 for Machine lnguage (CO)
        Bit 4       1 for ROM file
        Bit 3       1 for invisibile file
        Bit 2         reserved for future use
        Bit 1         reserved for future use
        Bit 0         internal use only
    

Function Name	Description	Entry conditions	Exit conditions	Entry Address (Hex)
MAKTXT	Create a text file	filename (max. 8 bytes) must be stored in FILNAM (0FC93). 'DO' extension not required	HL = TOP address of new file DE = address of Directory entry (Flag) Carry set if file already exits, reset if new file	220F
CHKDC	Search for file in directory	DE = address of filename to find (ASCII filename + 0 byte terminator	HL = start address (TOP) of file Z Flag -- 0 (file found), 1 file not found	5AA9
GTXTTB	Get top address of file	HL = address of directory entry for file	HL = Top start address of file	5AE3
KILASC	Kill a text (DO) file	DE = file TOP start address HL = address of directory entry (flag)	none	1FBE
INSCHR	Insert a character in a file	A = character to insert HL = address to insert character	HL = +1 Carry -- set if out of memory	6B61
MAKHOL	Insert a specified number of spaces in a file	BC = number of spaces to insert HL = address to insert spaces	HL & BC are preserved Carry -- set if out of memory	6B6D
MASDEL	Delete specified number of characters	BC = number of characters to delete HL = address of deletion	HL & BC are preserved	6B9F

Other Routines

Function Name	Description	Entry conditions	Exit conditions	Entry address (HEX)
INITIO	Cold start reset	none	none	6CD6
IOINIT	Warm start reset	none	none	6CE0
MENU	Go to Main Menu	none	none	5797
MUSIC	Make tone (See owner's manual for frequency and duration information)	DE = frequency B = duration	none	72C5
TIME	Read system TIME	HL = address of 8 byte area for TIME	HL => TIME (hh:mm:ss)	190F
DATE	Read system DATE	HL = address of 8-byte area for DATE	HL => DATE (mm/dd/yy)	192F
DAY	READ system DAY of the week	HL = address of 3 byte area for DAY	HL => DAY (ddd)	1962