80-Bus News

  

November-December 1983, Volume 2, Issue 6











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PRESTEL for Nascom 2 & Gemini IVC M-B0 5 Dee 1983 22:22 PAGE 1+6 PRESTEL for Nascom 2 & Gemini IVC M-80 5 Dee 1983 22:22 PAGE 1-7 PREST V8, PRESTEL terminal program. RL. 22/11/83 PREST V8, PRESTEL terminal program. RL. 22/11/83

0336 Do exx POLLU – Polls the UART and moves any

% O3B7 18 FF 1d e,Offh 3 poll for “C 5 waiting character to (DE) O3B9 OE 06 ld c,condir 3; {st of a DEL string is converted to O7h and O3BB cD 0005 call jbdos 3 rest of string is suppressed. Simplifies subsequent O3BE Dg exx ; handling by GEMPEN and saves buffer space. O3BF BT or a 03C0 28 05 jr z,de10 o40D DB 02 POLLU: IN A, (UARTS) 0302 FE 03 ep cone O40F 17 RLA 0304 CA 0374 dip z,exit 0410 DO RET NC 0307 3A O3D3 del0: id a,(ms) 0444 3A 0121 ld a,(delfig) O3CA E3 deli: ex (sp),hl 0414 BT or a O3CB E3 ex (sp),hl 0415 28 OF jr 2z,pollut o3cc 3D dec a 0417 DB O1 in a,(uartd) 3 flg is set O3CD 20 FB jr nz,dell 0419 E6 7F and 7fh O3CF 10 F6 djnz deld 041B FE 7F ep 7fh ; suppress if DEL 0301 et pop be O41D ca ret z O3D2 cg ret 0418 F5 push af O3D3 4B ms: defb 75 3; for 4MHz, no waits O41F AF xor a 0420 32 0121 ld (delfig),a ; reset flg if not O3D4 38 10 pulse: 1d a,10H } open dial relay 0423 Fi pop af O3D6 D3 04 out (dialpd),a 0424 18 OD jr pollu2 03D8 CD O3AB eall dly66 O3DB 3E 30 id a,30H 3 close dial relay 0426 DB O41 POLLU1: IN A, (UARTD) O3DD D3 04 out (dialpd),a 0428 E6 7F AND TFH O3DF CD 0382 call dly33 042A FE TF ep 7fh O3E2 cg ret 0420 20 05 ir Cette 0425 32 0121 ld (delflg),a 3; set flg & convert.. ; Connect line and on to term routine 0433 * o7 pounue i aT oA s++to bell symbol 3 <- from "T" command : DD DE), 03E3 3B 30 conlin: 14 a,30h 0434 13 INc DE 0385 D3 04 out (dialpd),a 0435 TA LD A,D 0436 PE 02 cp 2 ; Clear screen, and set limit 0437 LIMIT EQU $-4 3 modified on init 0438 DS RET C O3E7 3B 1A DTERM: 1d a,tah 0439 28 02 JR 2, SWITCH O3E9 CD O45F call putvid 043B 1B DEC DE O3EC 3A 0007 LD A, (7) 043C cg RET O3EF 3D DEC A O3FO 32 0437 LD (LIMIT) ,A OAs x 69 switch: nop 3 only pass once d a,0c9h ; Start of main processing loop 0440-32 0430 ld (switeh),a ; Uses a PIFO buffer to handle the data 0443 38 1B id _a,1bh ; <DE> = Input pointer <HL> = Output pointer es sr ‘o au puyvad invert a, 3 Invert screen as.. O3F3 11 0502 LOOPO: LD DE, BUFFER+2 O4aD 69 O45F call putvid j+-buffer full warniing O3F6 21 0502 LD HL, BUFFER+2 re O3F9 CD O46C LOOP1: CALL CONST O3FC C4 0448 CALL NZ, SEROUT ; SEROUT – Outputs the character in <A> to O3FF ES PUSH «HL ; the serial port. 0400 B7 OR A 0401 ED 52 SBC HL, DE 0448 FS SEROUT: PUSH AP 0403 Bt PoP HL O44F DB O02 SEROO: IN A, (UARTS) 0404-28 FS JR Z,LOOP1 ; original (non-store).. 0451 = -B6 40 AND 40H 0406 TE LD A,(HL) 5 version is jr z,loop0 0453 28 FA JR 2, SEROO 0407 23 INC HL 0408 CD O45F CALL PUTVID \

O40B 18 EC oR LOOP1


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