.ENTRY \ --- Mod: Code removed for Elite-A: ------------------> \IF _STH_DISC OR _IB_DISC \ \ JSR PROT1 \ Call PROT1 to calculate checksums into CHKSM \ \ELIF _SRAM_DISC \ \ JSR PROT4 \ Fetch the address of the keyboard translation table \ \ before calling PROT1 to calculate checksums into CHKSM \ \ENDIF \ \ LDA #144 \ Call OSBYTE with A = 144, X = 255 and Y = 0 to move \ LDX #255 \ the screen down one line and turn screen interlace on \ JSR OSB \ --- And replaced by: --------------------------------> CLI \ Enable interrupts LDA #144 \ Call OSBYTE with A = 144, X = 255 and Y = 1 to move LDX #255 \ the screen down one line and turn screen interlace off LDY #1 JSR OSBYTE \ --- End of replacement ------------------------------> LDA #LO(B%) \ Set the low byte of ZP(1 0) to point to the VDU code STA ZP \ table at B% LDA #HI(B%) \ Set the high byte of ZP(1 0) to point to the VDU code STA ZP+1 \ table at B% LDY #0 \ We are now going to send the N% VDU bytes in the table \ at B% to OSWRCH to set up the special mode 4 screen \ that forms the basis for the split-screen mode .loop1 LDA (ZP),Y \ Pass the Y-th byte of the B% table to OSWRCH JSR OSWRCH INY \ Increment the loop counter CPY #N% \ Loop back for the next byte until we have done them BNE loop1 \ all (the number of bytes was set in N% above) JSR PLL1 \ Call PLL1 to draw Saturn \ --- Mod: Code removed for Elite-A: ------------------> \ LDA #16 \ Call OSBYTE with A = 16 and X = 3 to set the ADC to \ LDX #3 \ sample 3 channels from the joystick/Bitstik \ JSR OSBYTE \ --- And replaced by: --------------------------------> LDA #16 \ Call OSBYTE with A = 16 and X = 2 to set the ADC to LDX #2 \ sample 2 channels from the joystick JSR OSBYTE \ --- End of replacement ------------------------------> LDA #&60 \ Store an RTS instruction in location &0232 STA &0232 LDA #&02 \ Point the NETV vector to &0232, which we just filled STA NETV+1 \ with an RTS LDA #&32 STA NETV LDA #190 \ Call OSBYTE with A = 190, X = 8 and Y = 0 to set the LDX #8 \ ADC conversion type to 8 bits, for the joystick JSR OSB \ --- Mod: Code removed for Elite-A: ------------------> \IF _STH_DISC OR _IB_DISC \ \ LDA #200 \ Call OSBYTE with A = 200, X = 0 and Y = 0 to enable \ LDX #0 \ the ESCAPE key and disable memory clearing if the \ JSR OSB \ BREAK key is pressed \ \ELIF _SRAM_DISC \ \ LDA #219 \ Store 219 in location &9F. This gets checked by the \ STA &9F \ TITLE routine in the main docked code as part of the \ \ copy protection (the game hangs if it doesn't match) \ \ \ \ This is normally done in the OSBmod routine, but the \ \ sideways RAM variant doesn't call OSBmod as that part \ \ of the copy protection is disabled, so we set the \ \ value of location &BF here instead \ \ NOP \ Pad out the code so it takes up the same amount of \ NOP \ space as in the original version \ NOP \ \ENDIF \ --- And replaced by: --------------------------------> LDA #200 \ Call OSBYTE with A = 200, X = 3 and Y = 0 to disable LDX #3 \ the ESCAPE key and clear memory if the BREAK key is JSR OSB \ pressed \ --- End of replacement ------------------------------> LDA #13 \ Call OSBYTE with A = 13, X = 0 and Y = 0 to disable LDX #0 \ the "output buffer empty" event JSR OSB LDA #225 \ Call OSBYTE with A = 225, X = 128 and Y = 0 to set LDX #128 \ the function keys to return ASCII codes for SHIFT-fn JSR OSB \ keys (i.e. add 128) \ --- Mod: Code removed for Elite-A: ------------------> \ LDA #12 \ Set A = 12 and X = 0 to pretend that this is an \ LDX #0 \ innocent call to OSBYTE to reset the keyboard delay \ \ and auto-repeat rate to the default, when in reality \ \ the OSB address in the next instruction gets modified \ \ to point to OSBmod \ \.OSBjsr \ \IF _STH_DISC OR _IB_DISC \ \ JSR OSB \ This JSR gets modified by code inserted into PLL1 so \ \ that it points to OSBmod instead of OSB, so this \ \ actually calls OSBmod to calculate some checksums \ \ELIF _SRAM_DISC \ \ NOP \ The sideways RAM variant has this part of the copy \ NOP \ protection disabled, so pad out the code so it takes \ NOP \ up the same amount of space as in the original version \ \ENDIF \ --- End of removed code -----------------------------> LDA #13 \ Call OSBYTE with A = 13, X = 2 and Y = 0 to disable LDX #2 \ the "character entering buffer" event JSR OSB LDA #4 \ Call OSBYTE with A = 4, X = 1 and Y = 0 to disable LDX #1 \ cursor editing, so the cursor keys return ASCII values JSR OSB \ and can therefore be used in-game LDA #9 \ Call OSBYTE with A = 9, X = 0 and Y = 0 to disable LDX #0 \ flashing colours JSR OSB \ --- Mod: Code added for Elite-A: --------------------> LDA #119 \ Call OSBYTE with A = 119 to close any *SPOOL or *EXEC JSR OSBYTE \ files \ --- End of added code -------------------------------> JSR PROT3 \ Call PROT3 to do more checks on the CHKSM checksum LDA #&00 \ Set the following: STA ZP \ LDA #&11 \ ZP(1 0) = &1100 STA ZP+1 \ P(1 0) = TVT1code LDA #LO(TVT1code) STA P LDA #HI(TVT1code) STA P+1 \ --- Mod: Code removed for Elite-A: ------------------> \ JSR MVPG \ Call MVPG to move and decrypt a page of memory from \ \ TVT1code to &1100-&11FF \ --- And replaced by: --------------------------------> JSR MVPG \ Call MVPG to move a page of memory from TVT1code to \ &1100-&11FF LDA #LO(S%+11) \ Point BRKV to the fifth entry in the main docked STA BRKV \ code's S% workspace, which contains JMP BRBR LDA #HI(S%+11) STA BRKV+1 \ --- End of replacement ------------------------------> LDA #&00 \ Set the following: STA ZP \ LDA #&78 \ ZP(1 0) = &7800 STA ZP+1 \ P(1 0) = DIALS LDA #LO(DIALS) \ X = 8 STA P LDA #HI(DIALS) STA P+1 LDX #8 \ --- Mod: Code removed for Elite-A: ------------------> \ JSR MVBL \ Call MVBL to move and decrypt 8 pages of memory from \ \ DIALS to &7800-&7FFF \ \ SEI \ Disable interrupts while we set up our interrupt \ \ handler to support the split-screen mode \ \ LDA VIA+&44 \ Read the 6522 System VIA T1C-L timer 1 low-order \ STA &0001 \ counter (SHEILA &44), which decrements one million \ \ times a second and will therefore be pretty random, \ \ and store it in location &0001, which is among the \ \ main game code's random seeds (so this seeds the \ \ random number generator for the main game) \ \ LDA #%00111001 \ Set 6522 System VIA interrupt enable register IER \ STA VIA+&4E \ (SHEILA &4E) bits 0 and 3-5 (i.e. disable the Timer1, \ \ CB1, CB2 and CA2 interrupts from the System VIA) \ \ LDA #%01111111 \ Set 6522 User VIA interrupt enable register IER \ STA VIA+&6E \ (SHEILA &6E) bits 0-7 (i.e. disable all hardware \ \ interrupts from the User VIA) \ \ LDA IRQ1V \ Copy the current IRQ1V vector address into VEC(1 0) \ STA VEC \ LDA IRQ1V+1 \ STA VEC+1 \ \ LDA #LO(IRQ1) \ Set the IRQ1V vector to IRQ1, so IRQ1 is now the \ STA IRQ1V \ interrupt handler \ LDA #HI(IRQ1) \ STA IRQ1V+1 \ \ LDA #VSCAN \ Set 6522 System VIA T1C-L timer 1 high-order counter \ STA VIA+&45 \ (SHEILA &45) to VSCAN (57) to start the T1 counter \ \ counting down from 14622 at a rate of 1 MHz \ \ CLI \ Re-enable interrupts \ --- And replaced by: --------------------------------> JSR MVBL \ Call MVBL to move 8 pages of memory from DIALS to \ &7800-&7FFF \ --- End of replacement ------------------------------> LDA #&00 \ Set the following: STA ZP \ LDA #&61 \ ZP(1 0) = &6100 STA ZP+1 \ P(1 0) = ASOFT LDA #LO(ASOFT) STA P LDA #HI(ASOFT) STA P+1 JSR MVPG \ Call MVPG to move a page of memory from ASOFT to \ &6100-&61FF LDA #&63 \ Set the following: STA ZP+1 \ LDA #LO(ELITE) \ ZP(1 0) = &6300 STA P \ P(1 0) = ELITE LDA #HI(ELITE) STA P+1 JSR MVPG \ Call MVPG to move a page of memory from ELITE to \ &6300-&63FF LDA #&76 \ Set the following: STA ZP+1 \ LDA #LO(CpASOFT) \ ZP(1 0) = &7600 STA P \ P(1 0) = CpASOFT LDA #HI(CpASOFT) STA P+1 \ --- Mod: Code removed for Elite-A: ------------------> \ JSR MVPG \ Call MVPG to move and decrypt a page of memory from \ \ CpASOFT to &7600-&76FF \ \ LDA #&00 \ Set the following: \ STA ZP \ \ LDA #&04 \ ZP(1 0) = &0400 \ STA ZP+1 \ P(1 0) = WORDS \ LDA #LO(WORDS) \ X = 4 \ STA P \ LDA #HI(WORDS) \ STA P+1 \ LDX #4 \ \ JSR MVBL \ Call MVBL to move and decrypt 4 pages of memory from \ \ WORDS to &0400-&07FF \ \ LDX #35 \ We now want to copy the disc catalogue routine from \ \ CATDcode to CATD, so set a counter in X for the 36 \ \ bytes to copy \ \.loop2 \ \ LDA CATDcode,X \ Copy the X-th byte of CATDcode to the X-th byte of \ STA CATD,X \ CATD \ \ DEX \ Decrement the loop counter \ \ BPL loop2 \ Loop back to copy the next byte until they are all \ \ done \ \ LDA &76 \ Set the drive number in the CATD routine to the \ STA CATBLOCK \ contents of &76, which gets set in ELITE3 \ --- And replaced by: --------------------------------> JSR MVPG \ Call MVPG to move a page of memory from CpASOFT to \ &7600-&76FF \ --- End of replacement ------------------------------> FNE 0 \ Set up sound envelopes 0-3 using the FNE macro FNE 1 FNE 2 FNE 3 LDX #LO(MESS1) \ Set (Y X) to point to MESS1 ("DIR E") LDY #HI(MESS1) JSR OSCLI \ Call OSCLI to run the OS command in MESS1, which \ changes the disc directory to E \ --- Mod: Code removed for Elite-A: ------------------> \ LDA #LO(LOAD) \ Set the following: \ STA ZP \ \ LDA #HI(LOAD) \ ZP(1 0) = LOAD \ STA ZP+1 \ P(1 0) = LOADcode \ LDA #LO(LOADcode) \ STA P \ LDA #HI(LOADcode) \ STA P+1 \ \ LDY #0 \ We now want to move and decrypt one page of memory \ \ from LOADcode to LOAD, so set Y as a byte counter \ \.loop3 \ \ LDA (P),Y \ Fetch the Y-th byte of the P(1 0) memory block \ \IF _STH_DISC OR _IB_DISC \ \ EOR #&18 \ Decrypt it by EOR'ing with &18 \ \ELIF _SRAM_DISC \ \ EOR CHKSM \ Decrypt it by EOR'ing with the checksum value \ \ENDIF \ \ STA (ZP),Y \ Store the decrypted result in the Y-th byte of the \ \ ZP(1 0) memory block \ \ DEY \ Decrement the byte counter \ \ BNE loop3 \ Loop back to copy the next byte until we have done a \ \ whole page of 256 bytes \ \ JMP LOAD \ Jump to the start of the routine we just decrypted \ --- And replaced by: --------------------------------> LDA #%11110000 \ Set the Data Direction Register (DDR) of port B of the STA VIA+&62 \ user port so we can read the buttons on the Delta 14B \ joystick, using PB4 to PB7 as output (so we can write \ to the button columns to select the column we are \ interested in) and PB0 to PB3 as input (so we can read \ from the button rows) LDA #0 \ Set HFX = 0 STA HFX STA LASCT \ Set LASCT = 0 LDA #&FF \ Set ESCP = &FF so we show the palette for when we have STA ESCP \ an escape pod fitted (i.e. black, red, white, cyan) SEI \ Disable interrupts while we set up our interrupt \ handler to support the split-screen mode LDA VIA+&44 \ If the STA instruction were not commented out, then \STA &0001 \ this would set location &0001 among the random number \ seeds to a pretty random number (i.e. the value of the \ 6522 System VIA T1C-L timer 1 low-order counter), but \ as the STA is commented out, this has no effect LDA #%00111001 \ Set 6522 System VIA interrupt enable register IER STA VIA+&4E \ (SHEILA &4E) bits 0 and 3-5 (i.e. disable the Timer1, \ CB1, CB2 and CA2 interrupts from the System VIA) LDA #%01111111 \ Set 6522 User VIA interrupt enable register IER STA VIA+&6E \ (SHEILA &6E) bits 0-7 (i.e. disable all hardware \ interrupts from the User VIA) LDA IRQ1V \ Copy the current IRQ1V vector address into VEC(1 0) STA VEC LDA IRQ1V+1 STA VEC+1 LDA #LO(IRQ1) \ Set the IRQ1V vector to IRQ1, so IRQ1 is now the STA IRQ1V \ interrupt handler LDA #HI(IRQ1) STA IRQ1V+1 LDA #VSCAN \ Set 6522 System VIA T1C-L timer 1 high-order counter STA VIA+&45 \ (SHEILA &45) to VSCAN (57) to start the T1 counter \ counting down from 14622 at a rate of 1 MHz CLI \ Re-enable interrupts LDA #0 \ Call OSBYTE with A = 0 and X = 1 to fetch bit 0 of the LDX #1 \ operating system version into X JSR OSBYTE CPX #3 \ If X =< 3 then this is not a BBC Master, so jump to BCC not_master \ not_master to continue loading the BBC Micro version \ This is a BBC Master, so now we copy the block of \ Master-specific filing system code from to_dd00 to \ &DD00 (so we copy the following routines: do_FILEV, \ do_FSCV, do_BYTEV, set_vectors and old_BYTEV) LDX #0 \ Set up a counter in X for the copy .cpmaster LDA to_dd00,X \ Copy the X-th byte of to_dd00 to &DD00 STA &DD00,X INX \ Increment the loop counter CPX #dd00_len \ Loop back until we have copied all the bytes in the BNE cpmaster \ to_dd00 block (as the length of the block is set in \ dd00_len below) LDA #143 \ Call OSBYTE 143 to issue a paged ROM service call of LDX #&21 \ type &21 with argument &C0, which is the "Indicate LDY #&C0 \ static workspace in 'hidden' RAM" service call. This JSR OSBYTE \ call returns the address of a safe place that we can \ use within the memory bank &C000-&DFFF, and returns \ the start location in (Y X) \ We now modify the savews routine so that when it's \ called, it copies the first three pages from the &C000 \ workspace to this safe place, and then copies the MOS \ character set into the first three pages of &C000, so \ the character printing routines can use them \ We also modify the restorews routine in a similar way, \ so that when it's called, it copies the three pages \ from the safe place back into the first three pages \ of &C000, thus restoring the filing system workspace STX put0+1 \ Modify the low byte of the workspace save address in STX put1+1 \ the savews routine to that of (Y X) STX put2+1 STX get0+1 \ Modify the low byte of the workspace restore address STX get1+1 \ in the restorews routine to that of (Y X) STX get2+1 STY put0+2 \ Modify the high byte of the workspace save address of \ the first page in the savews routine to that of (Y X) STY get0+2 \ Modify the high byte of the workspace restore address \ of the first page in the restorews routine to that of \ (Y X) INY \ Increment Y so that (Y X) points to the second page, \ i.e. (Y+1 X) STY put1+2 \ Modify the high byte of the workspace save address of \ the second page in the savews routine to (Y+1 X) STY get1+2 \ Modify the high byte of the workspace restore address \ of the second page in the restorews routine to that of \ (Y+1 X) INY \ Increment Y so that (Y X) points to the third page, \ i.e. (Y+2 X) STY put2+2 \ Modify the high byte of the workspace save address of \ the third page in the savews routine to (Y+2 X) STY get2+2 \ Modify the high byte of the workspace restore address \ of the third page in the restorews routine to that of \ (Y+2 X) LDA FILEV \ Set old_FILEV(1 0) to the existing address for FILEV STA old_FILEV+1 \ (this modifies the JMP instruction in the do_FILEV LDA FILEV+1 \ routine) STA old_FILEV+2 LDA FSCV \ Set old_FSCV(1 0) to the existing address for FSCV STA old_FSCV+1 \ (this modifies the JMP instruction in the do_FILEV LDA FSCV+1 \ routine) STA old_FSCV+2 LDA BYTEV \ Set old_BYTEV(1 0) to the existing address for BYTEV STA old_BYTEV+1 \ (this modifies the JMP instruction in the old_BYTEV LDA BYTEV+1 \ routine) STA old_BYTEV+2 IF _BUG_FIX JSR savews \ The do_FILEV handler starts by restoring the filing \ system workspace, so we need to save it first so the \ handler will work ENDIF JSR set_vectors \ Call set_vectors to update FILEV, FSCV and BYTEV to \ point to the new handlers in do_FILEV, do_FSCV and \ do_BYTEV .not_master LDA #234 \ Call OSBYTE with A = 234, X = 0 and Y = &FF, which LDY #&FF \ detects whether Tube hardware is present, returning LDX #0 \ X = 0 (not present) or X = &FF (present) JSR OSBYTE TXA \ Copy the result of the Tube check from X into A BNE tube_go \ If X is non-zero then we are running this over the \ Tube, so jump to tube_go to set up the Tube version \ If we get here then we are not running on a 6502 \ Second Processor LDA #172 \ Call OSBYTE 172 to read the address of the MOS LDX #0 \ keyboard translation table into (Y X) LDY #&FF JSR OSBYTE STX TRTB% \ Store the address of the keyboard translation table in STY TRTB%+1 \ TRTB%(1 0) LDA #&00 \ Set the following: STA ZP \ LDA #&04 \ ZP(1 0) = &0400 STA ZP+1 \ P(1 0) = WORDS LDA #LO(WORDS) \ X = 4 STA P LDA #HI(WORDS) STA P+1 LDX #4 JSR MVBL \ Call MVBL to move 4 pages of memory from WORDS to \ &0400-&07FF LDA #LO(S%+6) \ Point WRCHV to the third entry in the main docked STA WRCHV \ code's S% workspace, which contains JMP CHPR LDA #HI(S%+6) STA WRCHV+1 LDA #LO(LOAD) \ Set the following: STA ZP \ LDA #HI(LOAD) \ ZP(1 0) = LOAD STA ZP+1 \ P(1 0) = LOADcode LDA #LO(LOADcode) STA P LDA #HI(LOADcode) STA P+1 JSR MVPG \ Call MVPG to move a page of memory from LOADcode to \ LOAD LDY #35 \ We now want to copy the iff_index routine from \ iff_index_code to iff_index, so set a counter in Y \ for the 36 bytes to copy .copy_d7a LDA iff_index_code,Y \ Copy the X-th byte of iff_index_code to the X-th byte STA iff_index,Y \ of iff_index DEY \ Decrement the loop counter BPL copy_d7a \ Loop back to copy the next byte until they are all \ done JMP LOAD \ Jump to the start of the LOAD routine we moved above, \ to run the game .tube_go LDA #172 \ Call OSBYTE 172 to read the address of the MOS LDX #0 \ keyboard translation table into (Y X) LDY #&FF JSR OSBYTE STX key_tube \ Store the address of the keyboard translation table in STY key_tube+1 \ key_tube(1 0) \LDX #LO(tube_400) \ These instructions are commented out in the original \LDY #HI(tube_400) \ source \LDA #1 \JSR &0406 \LDA #LO(WORDS) \STA &72 \LDA #HI(WORDS) \STA &73 \LDX #&04 \LDY #&00 \.tube_wr \LDA (&72),Y \JSR tube_wait \BIT tube_r3s \BVC tube_wr \STA tube_r3d \INY \BNE tube_wr \INC &73 \DEX \BNE tube_wr \LDA #LO(tube_wrch) \STA WRCHV \LDA #HI(tube_wrch) \STA WRCHV+&01 LDX #LO(tube_run) \ Set (Y X) to point to tube_run ("R.2.H") LDY #HI(tube_run) JMP OSCLI \ Call OSCLI to run the OS command in tube_run, which \ runs the I/O processor code in 2.H .tube_run EQUS "R.2.H" \ The OS command for running the Tube version's I/O EQUB 13 \ processor code in file 2.H (this command is short for \ "*RUN 2.H") \.tube_400 \ These instructions are commented out in the original \EQUD &0400 \ source \.tube_wait \JSR tube_wait2 \.tube_wait2 \JSR tube_wait3 \.tube_wait3 \RTS \ --- End of replacement ------------------------------>Name: Elite loader (Part 1 of 3) [Show more] Type: Subroutine Category: Loader Summary: Set up the split screen mode, move code around, set up the sound envelopes and configure the systemContext: See this subroutine in context in the source code References: No direct references to this subroutine in this source file
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Label ASOFT in subroutine Elite loader (Part 3 of 3)
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Variable B% (category: Drawing the screen)
VDU commands for setting the square mode 4 screen
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Configuration variable BRKV = &0202
The break vector that we intercept to enable us to handle and display system errors
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Configuration variable BYTEV = &020A
The BYTEV vector that we intercept on the BBC Master
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Label CpASOFT in subroutine Elite loader (Part 3 of 3)
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Label DIALS in subroutine Elite loader (Part 2 of 3)
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Label ELITE in subroutine Elite loader (Part 3 of 3)
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Configuration variable ESCP = &0386
The flag that determines whether we have an escape pod fitted, matching the address in the main game code
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Configuration variable FILEV = &0212
The FILEV vector that we intercept on the BBC Master
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Macro FNE (category: Sound)
Macro definition for defining a sound envelope
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Configuration variable FSCV = &021E
The FSCV vector that we intercept on the BBC Master
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Configuration variable HFX = &0348
A flag that toggles the hyperspace colour effect, matching the address in the main game code
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Subroutine IRQ1 (category: Drawing the screen)
The main screen-mode interrupt handler (IRQ1V points here)
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Configuration variable IRQ1V = &0204
The IRQ1V vector that we intercept to implement the split-screen mode
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Configuration variable LASCT = &0346
The laser pulse count for the current laser, matching the address in the main game code
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Subroutine LOAD (category: Loader)
Load the main docked code, set up various vectors, run a checksum and start the game
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Subroutine LOADcode (category: Loader)
Encrypted LOAD routine, bundled up in the loader so it can be moved to &0B00 to be run
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Variable MESS1 (category: Loader)
The OS command string for changing the disc directory to E
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Subroutine MVBL (category: Utility routines)
Move a multi-page block of memory
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Subroutine MVPG (category: Utility routines)
Move a page of memory
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Configuration variable N% = 67
N% is set to the number of bytes in the VDU table, so we can loop through them in part 1 below
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Configuration variable NETV = &0224
The NETV vector that we intercept as part of the copy protection
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Subroutine OSB (category: Utility routines)
A convenience routine for calling OSBYTE with Y = 0
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Configuration variable OSBYTE = &FFF4
The address for the OSBYTE routine
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Configuration variable OSCLI = &FFF7
The address for the OSCLI vector
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Configuration variable OSWRCH = &FFEE
The address for the OSWRCH routine
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Subroutine PLL1 (Part 1 of 3) (category: Drawing planets)
Draw Saturn on the loading screen (draw the planet)
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Subroutine PROT3 (category: Copy protection)
Part of the CHKSM copy protection checksum calculation
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Configuration variable S% = &11E3
The address of the main entry point workspace in the main game code
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Subroutine TVT1code (category: Loader)
Code block at &1100-&11E2 that remains resident in both docked and flight mode (palettes, screen mode routine and commander data)
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Configuration variable VEC = &7FFE
VEC is where we store the original value of the IRQ1 vector, matching the address in the elite-missile.asm source
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Configuration variable VIA = &FE00
Memory-mapped space for accessing internal hardware, such as the video ULA, 6845 CRTC and 6522 VIAs (also known as SHEILA)
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Configuration variable VSCAN = 57
Defines the split position in the split-screen mode
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Label WORDS in subroutine Elite loader (Part 2 of 3)
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Configuration variable WRCHV = &020E
The WRCHV vector that we intercept with our custom text printing routine
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Workspace ZP (category: Workspaces)
Important variables used by the loader
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Label copy_d7a is local to this routine
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Label cpmaster is local to this routine
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Subroutine iff_index (category: Dashboard)
Return the type index for this ship in the I.F.F. system
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Subroutine iff_index_code (category: Dashboard)
The iff_index routine, bundled up in the loader so it can be moved to &0D7A to be run
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Label loop1 is local to this routine
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Label not_master is local to this routine
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Subroutine old_BYTEV (category: Loader)
Call the default OSBYTE handler
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Subroutine savews (category: Loader)
Save the filing system workspace in a safe place and replace it with the MOS character set
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Subroutine set_vectors (category: Loader)
Set the FILEV, FSCV and BYTEV vectors to point to our custom handlers
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Subroutine to_dd00 (category: Loader)
BBC Master code for saving and restoring the MOS character set, bundled up in the loader so it can be moved to &DD00 to be run
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Label tube_go is local to this routine
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Variable tube_run is local to this routine
The OS command for running the Tube version's I/O