.DIS1 LSR A ; Set A = A / 16, so A is 0-31 LSR A LSR A .DIS2 CMP #32 ; Cap A to a maximum value of 31, so A is in the range BCC P%+4 ; 0 to 31 LDA #31 LDX dialc1,Y ; Set X to the low-value colour for indicator Y from the ; dialc1 table CMP dialle,Y ; If A < dialle for indicator Y, then this is a low BCC DI3 ; value that is below the threshold for this indicator, ; so jump to DI3 as we already have the correct colour LDX dialc2,Y ; If we get here then A > dialle for indicator Y, ; which is a high value that is on or above the ; threshold for this indicator, so set X to the ; high-value colour for indicator Y from the dialc2 ; table .DI3 CPX #$FF ; If the colour in X is not $FF, jump to DI4 BNE DI4 LDX K+2 ; If the colour in X is $FF, set X = K + 2, so X is ; either red, or flashing red-and-white if flashing ; colours are configured CLC ; Clear the C flag (though this doesn't seem to have any ; effect, as we do a comparison almost straight away ; that will override the C flag) .DI4 INY ; Increment Y to point to the next indicator, ready for ; the next indicator to be drawn PHA ; Store the indicator value in A on the stack, so we can ; retrieve it below ; If we have already drawn this indicator in a previous ; iteration of the main loop, then we will have stored ; the indicator value and colour in the dials and dialc ; tables, so we now check these to see whether we need ; to update the indicator ; ; If this is the first time we have drawn this indicator ; then the values in dials and dialc will be zero, to ; indicate that no bar is shown ; ; Note that as we just incremented Y, we need to fetch ; the values for this indicator from dials-1 + Y and ; dialc-1 + Y, for example CMP dials-1,Y ; If the indicator value in A does not match the BNE DI6 ; previous value for this indicator in dials, jump to ; DI6 to update the indicator TXA ; If the colour in X matches the previous colour in CMP dialc-1,Y ; dialc, then both the value and the colour of this BEQ DI8 ; indicator are unchanged, so jump to DI8 to return ; from the subroutine without drawing anything .DI6 TXA ; Store the new colour of the bar in the dialc table, LDX dialc-1,Y ; for use the next time the indicator is drawn, and STA dialc-1,Y ; set X to the previous colour LDA dials-1,Y ; Set A to the previous value of this indicator from ; the dials table JSR DIS7 ; Call DIS7 below to draw this indicator using its ; previous value and colour, which will remove it from ; the screen as we draw indicators using EOR logic LDX dialc-1,Y ; Set X to the new colour for the indicator, which we ; just stored in the dialc table PLA ; Retrieve the new indicator value from the stack and STA dials-1,Y ; store it in the dials table, for use the next time ; the indicator is drawn .DIS7 ; We now draw the indicator with the colour in X and ; the value in A STX COL ; Set the drawing colour to X LDX dialY-1,Y ; Set Y1 to the screen y-coordinate of the indicator STX Y1 ; from the dialY table (so this is the y-coordinate of ; the top line of the four-line indicator) LDX K ; Set X1 to K, so it contains the x-coordinate of the STX X1 ; left end of the indicator CLC ; Set X2 = K + A, so it contains the x-coordinate of the ADC K ; right end of the indicator bar (as we want to draw a AND #%11111110 ; bar of length A pixels) STA X2 ; ; We round this down to an even number to ensure that ; the two-bit colour pattern fits exactly (though this ; isn't strictly necessary as the HLOIN routine also ; does this) JSR P%+3 ; Call MSBARS twice to draw four pixel lines to form the JMP MSBARS ; indicator bar, returning from the subroutine using a ; tail call .DI8 PLA ; Retrieve the indicator value from the stack so we can ; return it in A .DIR1 RTS ; Return from the subroutineName: DIS1 [Show more] Type: Subroutine Category: Dashboard Summary: Update a bar-based indicator on the dashboardContext: See this subroutine in context in the source code References: This subroutine is called as follows: * DIALS (Part 4 of 4) calls DIS1 * DIALS (Part 4 of 4) calls via DIS1+2 * DIALS (Part 1 of 4) calls via DIS2 * DIALS (Part 3 of 4) calls via DIS2 * DIS5 calls via DIR1
The range of values shown on the indicator depends on which entry point is called. For the default entry point of DIS1, the range is 0-255 (as the value passed in A is one byte), while for DIS2 the range is 0-31.
Arguments: A The value to be shown on the indicator (so the larger the value, the longer the bar) Y The indicator number: * 0 = Speed indicator * 3 = Energy bank 4 (bottom) * 4 = Energy bank 3 * 5 = Energy bank 2 * 6 = Energy bank 1 (top) * 7 = Forward shield indicator * 8 = Aft shield indicator * 9 = Fuel level indicator * 10 = Altitude indicator * 11 = Cabin temperature indicator * 12 = Laser temperature indicator K The screen x-coordinate of the left end of the indicator K+2 The colour we should use for dangerous values
Returns: A The value to be shown on the indicator, scaled to fit into the range 0 to 31 Y Y is incremented to the next indicator number
Other entry points: DIS1+2 The range of the indicator is 0-63 (for the fuel indicator) DIS2 The range of the indicator is 0-31 (for the fuel and energy bank indicators) DIR1 Contains an RTS
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Label DI3 is local to this routine
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Label DI4 is local to this routine
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Label DI6 is local to this routine
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Label DI8 is local to this routine
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Label DIS7 is local to this routine
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Subroutine MSBARS (category: Dashboard)
Draw two horizontal lines as part of an indicator bar, from (X1, Y1+1) to (X2, Y1+1) and (X1, Y1+2) to (X2, Y1+2)
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Variable dialY (category: Dashboard)
The screen y-coordinate of the top-left corner of each indicator
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Variable dialc1 (category: Dashboard)
The colour for each indicator for values that are below the threshold in dialle
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Variable dialc2 (category: Dashboard)
The colour for each indicator for values that are on or above the threshold in dialle
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Variable dialle (category: Dashboard)
The threshold value for each indicator that defines low and high values, and therefore the low and high colours for the indicator
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Variable dials in workspace Option variables
Current dashboard indicator values