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Version: < b > 0.9.9< / b > < br >
Last Updated: < b > 2021-11-25< / b >
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< li > < a href = #addeventcallback > addEventCallback< / a > < / li >
< li > < a href = #removeeventcallback > removeEventCallback< / a > < / li >
< li > < a href = #addmemorycallback > addMemoryCallback< / a > < / li >
< li > < a href = #removememorycallback > removeMemoryCallback< / a > < / li >
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< li > < a href = #addeventcallback > addEventCallback< / a > < / li >
< li > < a href = #removeeventcallback > removeEventCallback< / a > < / li >
< li > < a href = #addmemorycallback > addMemoryCallback< / a > < / li >
< li > < a href = #removememorycallback > removeMemoryCallback< / a > < / li >
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< h2 id = addeventcallback > addEventCallback< / h2 >
< p > < strong > Syntax< / strong > < / p >
< pre > < code > emu.addEventCallback(function, type)
< / code > < / pre >
< p > < strong > Parameters< / strong > < br >
function - A Lua function.< br >
type - < em > Enum< / em > See < a href = ../apireference/enums.html#eventtype > eventType< / a > .< / p >
< p > < strong > Return value< / strong > < br >
Returns an integer value that can be used to remove the callback by calling < a href = #removeeventcallback > removeEventCallback< / a > .< / p >
< p > < strong > Description< / strong > < br >
Registers a callback function to be called whenever the specified event occurs.< br >
The callback function receives no parameters.< / p >
< h2 id = removeeventcallback > removeEventCallback< / h2 >
< p > < strong > Syntax< / strong > < / p >
< pre > < code > emu.removeEventCallback(reference, type)
< / code > < / pre >
< p > < strong > Parameters< / strong > < br >
reference - The value returned by the call to < a href = #addeventcallback > addEventCallback< / a > .< br >
type - < em > Enum< / em > See < a href = ../apireference/enums.html#eventtype > eventType< / a > .< / p >
< p > < strong > Return value< / strong > < br >
< em > None< / em > < / p >
< p > < strong > Description< / strong > < br >
Removes a previously registered callback function.< / p >
< h2 id = addmemorycallback > addMemoryCallback< / h2 >
< p > < strong > Syntax< / strong > < / p >
< pre > < code > emu.addMemoryCallback(function, type, startAddress [, endAddress])
< / code > < / pre >
< p > < strong > Parameters< / strong > < br >
function - A Lua function.< br >
type - < em > Enum< / em > See < a href = ../apireference/enums.html#memcallbacktype > memCallbackType< / a > < br >
startAddress - < em > Integer< / em > Start of the CPU memory address range to register the callback on.< br >
endAddress - (optional) < em > Integer< / em > End of the CPU memory address range to register the callback on.< / p >
< p > < strong > Return value< / strong > < br >
Returns an integer value that can be used to remove the callback by calling < a href = #removememorycallback > removeMemoryCallback< / a > .< / p >
< p > < strong > Description< / strong > < br >
Registers a callback function to be called whenever the specified event occurs.< br >
The callback function receives 2 parameters < code > address< / code > and < code > value< / code > that correspond to the address being written to or read from, and the value that is being read/written.< / p >
< p > For reads, the callback is called < em > after< / em > the read is performed.< br >
For writes, the callback is called < em > before< / em > the write is performed.< / p >
< p > If the callback returns an integer value, it will replace the value – you can alter the results of read/write operation using this. e.g:< / p >
< div class = highlight > < pre tabindex = 0 style = color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4 > < code class = language-lua data-lang = lua > < span style = color:#66d9ef > function< / span > < span style = color:#a6e22e > writeCallback< / span > (address, value)
< span style = color:#75715e > --This sets bit 0 to 0 for all CHR RAM writes< / span >
< span style = color:#66d9ef > return< / span > value < span style = color:#f92672 > & < / span > < span style = color:#ae81ff > 0xFE< / span >
< span style = color:#66d9ef > end< / span >
emu.addMemoryCallback(writeCallback, emu.memCallbackType.ppuWrite, < span style = color:#ae81ff > 0< / span > , < span style = color:#ae81ff > 0x1FFF< / span > )
< / code > < / pre > < / div > < h2 id = removememorycallback > removeMemoryCallback< / h2 >
< p > < strong > Syntax< / strong > < / p >
< pre > < code > emu.removeMemoryCallback(reference, type, startAddress [, endAddress])
< / code > < / pre >
< p > < strong > Parameters< / strong > < br >
reference - The value returned by the call to < a href = #addmemorycallback > addMemoryCallback< / a > .< br >
type - < em > Enum< / em > See < a href = ../apireference/enums.html#memcallbacktype > memCallbackType< / a > .< br >
startAddress - < em > Integer< / em > Start of the CPU memory address range to unregister the callback from.< br >
endAddress - (optional) < em > Integer< / em > End of the CPU memory address range to unregister the callback from.< / p >
< p > < strong > Return value< / strong > < br >
< em > None< / em > < / p >
< p > < strong > Description< / strong > < br >
Removes a previously registered callback function.< / p >
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