Memory Management (2)
PH111
CAS circuit
WRN
MRQN
RDN
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| NTSC | ||
LPH1 |
| 1/4 |
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NTPL
CL 0
GATE 0
VCC 0
GND 0
Colour VRAM |
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character. One byte of colour infonnation table is assign- |
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CPU |
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ed to each characters displayed on the TV screen. | memory | Controller |
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address |
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| $EOOO |
| PA | : Output | |
D7 | ATB |
| ATB: CGROM | $EOOl |
| Pe | : Input | |
| $E002 | 8255 | Pc | : Input/output mode controller | ||||
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D6 | FRONT | G | ||||||
address switch- |
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D5 | FRONT | R | ingbit | $E003 |
| Mode controller | ||
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D4 | FRONT | B |
| $E004 |
| Co | : Mode 3 | |
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D3 | Not used | $E005 |
| C, | : Mode 2 | |||
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| 8253 |
| (rate generator) | |
D2 | BACK | G |
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| $E006 |
| C2 | : Mode 0 | ||||
D1 | BACK | R |
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| $E007 |
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DO | BACK | B |
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BACK |
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$E008 | LS367 and | Tempo,joystick, HBLNK input | ||||||
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Character iqfonnation is stored in address $DOOQ. $D7FF and colour infonnation in $D80Q.$DFFF of the
VRAM.
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