IV? 7ce
The memory controller and the CRTC are contained in the single chip custom LSI (M60719).
Memory controller signal description
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| Pin No. | Signal name | IN/OUT |
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1 | AO |
| CPU address Bus | AO | |||
| l | l | IN |
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16 | A15 |
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| A15 | ||
17 | LPH1 | IN | Clock (17.7MHz) | <I> | |||
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18 | PHI | IN | CPU clock (3.55MHz) | cp | |||
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19 | CSEN | OUT | 8255, 8253, joystick enable | CSE | |||
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10 | CL | IN | GND | CL | |||
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21 | GATE | IN | GND | GATE | |||
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22 | CSON | OUT | Monitor ROM enable | CSO | |||
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23 | VCC | - | Power supply | 5V | |||
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24 | RASN | OUT | RAS | ||||
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25 | RFSN | IN | CPU refresh | RFSH | |||
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26 | PHIO | OUT | CPU clock create signal (3.55MHz) | cpo | |||
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27 | MRQN | IN | CPU memory request | MREQ | |||
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28 | 10RN | IN | CPU I/O request | IORQ | |||
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29 | RDN | IN | CPU read | RD | |||
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20 | WRN | IN | CPU write | WR | |||
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31 | RSTN | IN | Reset | RESET | |||
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32 | SEL | IN | DRAM row/column address switching signal | SEL | |||
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33 | VBLN | OUT | Vertical blanking signal (CRT) | VBLK | |||
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34 | HBLN | OUT | Horizontal blanking signal (CRT) | HBLK | |||
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35 | WATN | OUT | CPU wait | WA | |||
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36 | COLR | OUT | Colour | COLR | |||
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37 | PRCN | OUT | Printer I/O address select | PRC | |||
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38 | Q1 |
| Display: Address data output (Line Count Signals) | Ql | |||
| l | l | OUT | (Display address is indicated to the CG ROM together | l | ||
| 40 | Q3 |
| with PO - PlO). | Q3 | ||
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| 41 | NTPL | IN | NTSC/PAL system switching (PAL=L) | N/P | ||
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| 42 | BLNK | OUT | Timer clock | BLNK | ||
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| 43 | HSYN | OUT | Horizontal synchronizing signal | HSY | ||
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| 44 | ABC | OUT |
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| ABC | |
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| 45 | LOAD | OUT | Character, display start signal | LOAD | ||
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| 46 | PO | OUT | Display address signal | PO | ||
| l | ~ |
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| 52 | P6 |
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| 53 | GND | - | GND |
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| 54 | P7 |
| Display address signal | P7 | ||
| l | l | OUT |
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| 57 | PlO |
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| 58 | S157 | OUT | S157 | |||
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| 59 | SYNN | OUT | Vertical synchronizing signal | SYN | ||
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| 60 | CLKN | OUT | Character display shift register clock | CLK | ||
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