Call Fafh

AXBIN converts from ASCII to binary. Load the HL register pair with the address of the first ASCII character to be converted. On return the DE register contains the binary equivalent. The maximum number which can be converted is 65529. This routine is located at 1E5AH.

LD HL.XXXH ;XXXX is address ol char to be converted CALL IE5AH ;call convert routine LD A,(DE) ;Acc. contains the ;binary value

OUTSTR will output a string of characters from memory to the CRT. Load the HL register with the address of the first character. Characters are out-putted until either a OOH or 22H is found. OUTSTR is located at 28A7H. (Note: Since the addition of a disk I have found this routine may or may not work. It will work if the system is brought up in BASIC2, non disk based BASIC.)

VIDEO displays any character in the A' on the CRT. You must push the DE register onto the stack before calling this routine. It is located at 0033H.

PUSH DE .save DE

CALL 0033H display character

POP DE restore DE

PRNTR, the printer driver routine, located at 058DH, is CALLed from 003BH. This routine locates the printer at 37E8H, and checks its ready status by reading 37E8H for a 30H.

This routine is very poor because it is not useful with many printers other than Centronic's. (Radio Shack has assumed that a smart printer will be used.)

You can capture the routine and use your own by changing the address stored at 4026H and 4027H to the address of your printer driver. (Note: Be sure to PROTECT your printer driver program by answering the MEMORY SIZE question).

SCANKE scans the keyboard for an entry (key closure) and returns the ASCII value of the key in the 'A' register. SKANKE is located at 002BH, you must exchange registers before calling this routine.

EXX .save registers

CALL 002BH scan the keyboard EXX ;restore registers

AND 7FH .mask out bit 8

Cursor control table is located from 0506H to 0540H.

1. Backspace and delete character— 04CEH

2. Delete last character—04CE. HL point to video memory ol character

4 Cursor Off-04BDH

5. Convert to expanded characters— 04F6H

6. Backspace cursor—04DAH

6a. Advance cursor—04ECH

7. Down feed cursor—04E7H

8. Up feed cursor—04F1H

9 Cursor home—04C0H

10. Cursor to beginning of line—04A1H

11. Erase from cursor to end of line— 0573H

12 Clear all after cursor—067CH

Relocated to RAM on power up:

1 Vectors for interrupts—06D2 to 06E6H

2 Keyboard device control block—06E7-

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