34 lines
1022 B
Markdown
34 lines
1022 B
Markdown
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## Memory.jack
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This library provides two services: direct access to the computer's main memory (RAM), and allocation and recycling of memory blocks. The Hack RAM consists of 3840 words, each holding a 16-bit binary number.
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Don't be afraid of the limited memory size of "only" 3840 words. Let the heap start at address 1024 with `do Memory.init(1024,3839)` in the Sys.init(). This will leave 768 words of stack, which is surely enough to run tetris.
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| addr | segment |
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| --------- | ----------------------------- |
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| 0-15 | R0-R15 (SP,LCL,ARG,THIS,THAT) |
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| 16-255 | static |
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| 256-1023 | stack |
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| 1024-3839 | heap |
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| 4096-4111 | IO-devices |
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***
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### Project
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* Implement `Memory.jack`
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* Test in simulation:
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```
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$ cd 04_Memory_Test
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$ make
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$ cd ../00_HACK
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$ apio clean
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$ apio sim
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```
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* Check the content of special function register DEBUG0--DEBUG4.
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