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Added new RL11 component (work-in-progress)

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This commit is contained in:
Jeff Parsons 2016-10-24 16:28:48 -07:00 • committed by Jeff Parsons
commit 9e480d7574
24 changed files with 2760 additions and 585 deletions
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27
modules/shared/lib/diskapi.js
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@ -70,8 +70,16 @@ var DiskAPI = {
/*
* Common (supported) diskette formats
*
* For no particular reason that I can recall, each entry in DISK_FORMATS is an array of values in "CHS" order:
*
* [# cylinders, # heads, # sectors/track, # bytes/sector]
*
* If the 4th value is omitted, the sector size is assumed to be 512. The order of these "geometric" values mirrors
* the structure of our JSON-encoded disk images, which consist of an array of cylinders, each of which is an array of
* heads, each of which is an array of sector objects.
*/
DiskAPI.DISKETTE_FORMATS = {
DiskAPI.DISK_FORMATS = {
163840: [40,1,8], // media type 0xFE: 40 cylinders, 1 head (single-sided), 8 sectors/track, ( 320 total sectors x 512 bytes/sector == 163840)
184320: [40,1,9], // media type 0xFC: 40 cylinders, 1 head (single-sided), 9 sectors/track, ( 360 total sectors x 512 bytes/sector == 184320)
327680: [40,2,8], // media type 0xFF: 40 cylinders, 2 heads (double-sided), 8 sectors/track, ( 640 total sectors x 512 bytes/sector == 327680)
@ -83,7 +91,22 @@ DiskAPI.DISKETTE_FORMATS = {
/*
* The following are common early hard drive sizes, which we explicitly map to CHS values, since the BPB can mislead us when attempting to calculate total cylinders
*/
21368320:[615,4,17] // PC AT 20Mb hard drive (type 2)
21368320:[615,4,17], // PC AT 20Mb hard drive (type 2)
/*
* Assorted DEC disk pack formats.
*/
5242880: [256,2,40,256], // RL01K single-platter disk cartridge: 256 tracks, 2 heads, 40 sectors/track, 256 bytes/sector, for a total of 5242880 bytes
10485760:[512,2,40,256] // RL02K single-platter disk cartridge: 512 tracks, 2 heads, 40 sectors/track, 256 bytes/sector, for a total of 10485760 bytes
};
/*
* TODO: Eventually, our tools will need to support looking up disk formats by "model" rather than by raw disk size,
* because obviously multiple disk geometries can yield the same raw disk size. For each conflict that arises, I'll
* probably create a fake (approximate) disk size entry above, and then create a mapping to that approximate size below.
*/
DiskAPI.DISK_MODELS = {
"RL01": 5242880,
"RL02": 10485760
};
DiskAPI.MBR = {