ethonion10/v86
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

DMA auto should wrap around. Use Uint16 counters

Browse source
This commit is contained in:
Ernest Wong 2017-11-19 17:57:26 +13:00 committed by Fabian
parent c57e31eeea
commit 7581a4af5b
1 changed files with 16 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

20
src/dma.js
View file

@ -12,8 +12,8 @@ function DMA(cpu)
this.channel_page = new Uint8Array(8);
this.channel_addr = new Uint16Array(8);
this.channel_addr_init = new Uint16Array(8);
this.channel_count = new Int32Array(8);
this.channel_count_init = new Int32Array(8);
this.channel_count = new Uint16Array(8);
this.channel_count_init = new Uint16Array(8);
this.channel_mask = new Uint8Array(8);
this.channel_mode = new Uint8Array(8);
this.channel_on_unmask = [];
@ -316,6 +316,7 @@ DMA.prototype.do_write = function(buffer, start, len, channel, fn)
read_bytes = read_count,
addr = this.address_get_8bit(channel),
unfinished = false,
want_more = false,
autoinit = this.channel_mode[channel] & 0x10;
if(channel >= 5)
@ -336,6 +337,7 @@ DMA.prototype.do_write = function(buffer, start, len, channel, fn)
else if(len > read_bytes)
{
dbg_log("DMA attempted to read more than provided", LOG_DMA);
want_more = true;
}
if(start + read_bytes > buffer.byteLength)
@ -351,14 +353,24 @@ DMA.prototype.do_write = function(buffer, start, len, channel, fn)
if(!unfinished && autoinit)
{
dbg_log("DMA autoinit", LOG_DMA);
this.channel_addr[channel] = this.channel_addr_init[channel];
this.channel_count[channel] = this.channel_count_init[channel];
}
buffer.set(start,
this.cpu.mem8.subarray(addr, addr + read_count),
function() {
fn(false);
() =>
{
if(want_more && autoinit)
{
dbg_log("DMA continuing from start", LOG_DMA);
this.do_write(buffer, start, len - read_bytes, channel, fn);
}
else
{
fn(false);
}
}
);
}