;
;VERSION UAPPLE         (revised JUL 20, 1981)
;
;User routines for BSTAM version 4.3 or 4.4, for use with
;Apple CP/M with an Apple Communications Interface or
;a CCS 7710A Serial Interface in slot 2.
;       By Keith Petersen, W8SDZ
;
;DEFINE PORT ADDRESSES
;
STATUS  EQU     0E0A0H  ;COM. OR CCS CARD STATUS LOC.
DATA    EQU     0E0A1H  ;COM. CARD DATA - SLOT 2
;
;DEFINE ASCII CHARACTERS USED
;
CR      EQU     0DH
LF      EQU     0AH
;
;       IF YOU WISH TO USE OTHER REGISTERS SUCH AS HL,BC,DE
;       (NOT INCLUDING  SP  REGISTER)
;       BE SURE TO PUSH BSTAM'S REGISTERS ON TO STACK AND POP
;       THEM BACK OFF BEFORE RETURNING TO BSTAM.
;       THERE IS AMPLE ROOM TO PUSH ALL REGISTERS ONTO BSTAM'S
;       STACK, PLUS ROOM FOR 10 LEVELS OF CALL'S.
;
;       THERE ARE 300 BYTES OF USER SPACE AVAILABLE TO YOU.
;
;       THE JUMP'S CODED AT THE BEGINNING OF THIS PROGRAM
;       CANNOT BE MOVED IN ANY WAY.
;
BEGIN   ORG     103H
;
INITIL  JMP     INITIU  ;UART/USART INITIALATION ENTRY POINT
INSPORT JMP     INSPRU  ;STATUS PORT READ ENTRY POINT
ERRSET  JMP     ERRSTU  ;UART/USART ERROR RESET ENTRY POINT
INPORT  JMP     INPRTU  ;READ DATA PORT ENTRY POINT
OUTPORT JMP     OUTPRU  ;WRITE DATA PORT ENTRY POINT
;
INITIU  EQU     $
;       THIS IS THE UART/USART INITIALATION ROUTINE.
;       TO BE COMPATIBLE WITH MOST BSTAM USERS USE FOLLOWING
;       INITIALATION GUIDE LINES:
;       1. USE 1 STOP BIT       (OPTIONAL - 2)
;       2. USE 8 DATA BITS      (MUST)
;       3. USE 1 START BIT      (MUST)
;       4. USE 16X FOR CLOCK RATE       (MUST)
;       5. USE ASYNCHRONOUS MODE ONLY   (MUST)
;
       LDA     DATA    ;CLEAR DATA PORT
       LDA     DATA    ;AGAIN TO MAKE SURE
       CALL    SIGNON  ;TELL USER WHAT'S IMPLEMENTED
       RET             ;RETURN TO BSTAM
;
INSPRU  EQU     $
;       THIS IS THE STATUS READ PORT ROUTINE.
;       WHEN EXITING THIS ROUTINE BSTAM EXPECTS IN REGISTER A
;       THE FOLLOWING BITS TO BE SET IF NEEDED:
;       1. 20 BIT SET IF FRAMING ERROR
;       2. 10 BIT SET IF OVERRUN ERROR
;       3. 08 BIT SET IF PARITY  ERROR
;       4. 04 BIT SET IF TRANSMITTER EMPTY
;               IF YOUR UART/USART DOES NOT HAVE TRANSMITTER
;               EMPTY FEATURE, THEN ALLWAYS SET THIS BIT ON.
;       5. 02 BIT SET IF RECEIVER READY
;       6. 01 BIT SET IF TRANSMITTER READY
;       7. DO NOT SET THE 80 BIT OR 40 BIT
;
       LDA     STATUS  ;TBE = 02H, RDA = 01H
       RLC
       ANI     6       ;MASK OFF UNWANTED BITS
       ORI     1       ;BOGUS TBE BIT
       RET
;
ERRSTU  EQU     $
;       THIS IS THE ERROR RESET FOR UART/USART ROUTINE.
;       YOUR UART/USART MAY NOT NEED TO BE RESET IF FRAMING,
;       OVERRUN, OR PARITY ERROR IS FOUND. IF THIS IS YOUR
;       CASE, JUST DO A RETURN.
;
       RET             ;RETURN TO BSTAM
;
INPRTU  EQU     $
;       THIS IS THE READ DATA PORT ROUTINE.
;       BEFORE THIS ROUTINE IS ENTERED THE 02 BIT OF
;       STATUS READ ROUTINE MUST HAVE BEEN SET.
;       DO NOT CLEAR THE 80 BIT FROM THE DATA INPUT PORT.
;       RETURN WITH REGISTER A LOADED WITH INPUT DATA.
;
       LDA     DATA    ;GET DATA FROM PORT
       RET             ;RETURN TO BSTAM
;
OUTPRU  EQU     $
;       THIS IS THE WRITE DATA PORT ROUTINE.
;       BEFORE THIS ROUTINE IS ENTERED THE 04 BIT AND 01 BIT
;       OF STATUS READ MUST BE SET.
;       DO NOT CLEAR THE 80 BIT FROM THE DATA OUTPUT PORT.
;       REGISTER A CONTAINS THE OUTPUT DATA.
;
       STA     DATA    ;SEND DATA TO REMOTE CPU
       RET             ;RETURN TO BSTAM
;
MESSGE: DB      CR,LF,CR,LF
       DB      'Version for Apple II as of 7/20/81.',CR,LF
       DB      'For Apple Communications Interface or',CR,LF
       DB      'CCS 7710A Serial Interface in slot 2.',CR,LF,'$'
;
SIGNON: PUSH    B
       PUSH    D
       PUSH    H
       LXI     D,MESSGE
       MVI     C,9
       CALL    5               ;ANNOUNCE VERSION TO USER
       POP     H
       POP     D
       POP     B
       RET
;
       END