AMROM: Difference between revisions

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== Banks ==
== Banks ==
* CPU $8000-$ffff : 32 KB Switchable PRG ROM bank.
* CPU $8000-$ffff : 32 KB Switchable PRG ROM bank.
The AMROM board always have 4 PRG ROM banks.
The AMROM board always has 4 PRG ROM banks.


== Solder pad config ==
== Solder pad config ==
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                         -------
                         -------


This pinout is not compatible with standard 27C010 EPROMs, so to insert them in the board manual rewiring is needed.
This pinout is not compatible with standard 27C010 EPROMs. To insert them, manual rewiring is required.


* CHR-RAM - 64 kBit (8 KB x 8) (DIP-28) : Standard [[6264_static_ram|6264]] pinout.
* CHR-RAM - 64 KBit (8 KB x 8) (DIP-28) : Standard [[6264_static_ram|6264]] pinout.


* 74HC161 (DIP-16)
* 74HC161 (DIP-16)

Revision as of 14:03, 25 June 2010

AMROM refers to the NES-AMROM and HVC-AMROM boards of the AxROM category.

Overview

  • PRG ROM size: 128 KB
  • PRG ROM bank size: 32 KB
  • PRG RAM: None
  • CHR capacity: 8 KB RAM
  • CHR bank size: Not bankswitched
  • Nametable mirroring: Single-screen, mapper-selectable
  • Subject to bus conflicts: Yes

Banks

  • CPU $8000-$ffff : 32 KB Switchable PRG ROM bank.

The AMROM board always has 4 PRG ROM banks.

Solder pad config

No solder pad config is needed on the AMROM board.

Chips and pinout

  • PRG ROM - 1 MBit (128 KB x 8) (DIP-28) :
                       ---U---
                A15 - |01   28| - +5V
                A12 - |02   27| - A14
                A7  - |03   26| - A13
                A6  - |04   25| - A8 
                A5  - |05   24| - A9
                A4  - |06   23| - A11
                A3  - |07   22| - A16
                A2  - |08   21| - A10
                A1  - |09   20| - /CE (/ROMSEL)
                A0  - |10   19| - D7
                D0  - |11   18| - D6
                D1  - |12   17| - D5
                D2  - |13   16| - D4
                GND - |14   15| - D3
                       -------

This pinout is not compatible with standard 27C010 EPROMs. To insert them, manual rewiring is required.

  • CHR-RAM - 64 KBit (8 KB x 8) (DIP-28) : Standard 6264 pinout.
  • 74HC161 (DIP-16)