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Routines |
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Used by the routines at 27419 and 27144. Appends a font character bitmap (corresponding to the ASCII code in A) to the existing contents of a message graphic buffer.
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| 27110 | LD E,A | E=ASCII code (32-127) | ||||||
| 27111 | LD D,215 | Point DE at the appropriate entry in the table of font character bitmap widths at 55072 | ||||||
| 27113 | LD A,(DE) | A=width of the font character in pixels (1-5) | ||||||
| 27114 | LD B,A | Store this in B | ||||||
| 27115 | INC D | |||||||
| 27116 | LD A,(DE) | A=bit pattern for one pixel column of the font character | ||||||
| 27117 | CALL 27125 | Slide this into the message buffer | ||||||
| 27120 | DEC C | One fewer pixel column remaining in the message buffer | ||||||
| 27121 | DJNZ 27115 | Jump back until all pixel columns for the font character have been copied into the message buffer | ||||||
| 27123 | DEC C | One fewer pixel column remaining in the message buffer | ||||||
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This entry point is used by the routine at 27419.
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| 27124 | XOR A | A=0 (blank pixel column) | ||||||
| 27125 | EXX | |||||||
| 27126 | PUSH HL | |||||||
| 27127 | LD C,8 | 8 pixels per column | ||||||
| 27129 | LD B,8 | 8 bytes per pixel row (this is LD B,32 during startup; see 21408) | ||||||
| 27131 | RRCA | Push a pixel into the carry flag | ||||||
| 27132 | RL (HL) | Drag the pixel into the message buffer and shove the existing pixels one place to the left | ||||||
| 27134 | DEC HL | |||||||
| 27135 | DJNZ 27132 | |||||||
| 27137 | DEC C | |||||||
| 27138 | JR NZ,27129 | Jump back to collect the next pixel up | ||||||
| 27140 | POP HL | Restore the address of the last byte in the message buffer to HL' | ||||||
| 27141 | EXX | |||||||
| 27142 | RET | |||||||
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