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Fix 9th dot replication in 8-dot fonts

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This commit is contained in:
Jeff Parsons 2015-06-05 10:12:46 -07:00
commit aa98f63f47
2 changed files with 23 additions and 25 deletions
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12
modules/pcjs/lib/debugger.js
View file

@ -4511,8 +4511,8 @@ if (DEBUGGER) {
}
var port = this.parseValue(sPort);
if (port !== undefined) {
var byte = this.bus.checkPortInputNotify(port);
this.println(str.toHexWord(port) + ": " + str.toHexByte(byte));
var bIn = this.bus.checkPortInputNotify(port);
this.println(str.toHexWord(port) + ": " + str.toHexByte(bIn));
}
};
@ -4807,10 +4807,10 @@ if (DEBUGGER) {
return;
}
var port = this.parseValue(sPort, "port #");
var byte = this.parseValue(sByte);
if (port !== undefined && byte !== undefined) {
this.bus.checkPortOutputNotify(port, byte);
this.println(str.toHexWord(port) + ": " + str.toHexByte(byte));
var bOut = this.parseValue(sByte);
if (port !== undefined && bOut !== undefined) {
this.bus.checkPortOutputNotify(port, bOut);
this.println(str.toHexWord(port) + ": " + str.toHexByte(bOut));
}
};

36
modules/pcjs/lib/video.js
View file

@ -2950,22 +2950,19 @@ Video.prototype.reset = function()
if (this.cardActive.addrBuffer && fRandomize) {
/*
* On the initial power-on, we initialize the video buffer to random characters,
* as a way of testing whether our font(s) were successfully loaded. It's assumed
* that our default display mode is a text mode, and that since this is a reset,
* the CRTC.START_ADDR registers are zero as well.
* On the initial power-on, we initialize the video buffer to random characters, as a way of testing
* whether our font(s) were successfully loaded. It's assumed that our default display mode is a text mode,
* and that since this is a reset, the CRTC.START_ADDR registers are zero as well.
*
* If this is an MDA device, then the buffer should reside at 0xB0000 through 0xB0FFF,
* for a total length of 4Kb (0x1000), where every even byte contains a character code,
* and every odd byte contains an attribute code. See the ATTR bit definitions above for
* applicable color, intensity, and blink values. On a CGA device, the buffer resides
* at 0xB8000 through 0xBBFFF, for a total length of 16Kb.
* If this is an MDA device, then the buffer should reside at 0xB0000 through 0xB0FFF, for a total length
* of 4Kb (0x1000), where every even byte contains a character code, and every odd byte contains an attribute
* code. See the ATTR bit definitions above for applicable color, intensity, and blink values. On a CGA
* device, the buffer resides at 0xB8000 through 0xBBFFF, for a total length of 16Kb.
*
* Note that the only valid MDA display mode (7) is the 80x25 text mode, which uses 4000
* bytes (2000 character bytes + 2000 attribute bytes), not all 4096 bytes; addrScreenLimit
* reflects the visible limit, not the physical limit. Also, as noted in updateScreen(),
* this simplistic calculation of the extent of visible screen memory is valid only for
* text modes; in general, it's safer to use cardActive.sizeBuffer as the extent.
* Note that the only valid MDA display mode (7) is the 80x25 text mode, which uses 4000 bytes (2000 character
* bytes + 2000 attribute bytes), not all 4096 bytes; addrScreenLimit reflects the visible limit, not the
* physical limit. Also, as noted in updateScreen(), this simplistic calculation of the extent of visible
* screen memory is valid only for text modes; in general, it's safer to use cardActive.sizeBuffer as the extent.
*/
var addrScreenLimit = this.cardActive.addrBuffer + this.cbScreen;
for (var addrScreen = this.cardActive.addrBuffer; addrScreen < addrScreenLimit; addrScreen += 2) {
@ -3154,10 +3151,11 @@ Video.prototype.onLoadSetFonts = function(sFontFile, sFontData, nErrorCode)
* that give continuous lines and filled areas. This is unusual for a display with a 9x14 character box
* because the character generator provides a row only eight dots wide. On most displays, a blank 9th
* dot is then inserted between characters. On the monochrome display, there is circuitry that duplicates
* the 8th dot into the 9th dot position for characters whose ASCII codes are 0xB0 through 0xDF."
* the 8th dot into the 9th dot position for characters whose ASCII codes are 0xB0 [sic] through 0xDF."
*
* The only question is: is the range actually 0xC0-0xDF, or 0xB0-0xDF??? I'll assume the latter, since
* 0xB0 is where the line-drawing/area-fill characters appear to begin.
* However, the above text is mistaken about the start of the range. While there ARE line-drawing characters
* in the range 0xB0-0xBF, none of them extend all the way to the left edge; IBM carefully segregated them.
* And in fact, characters 0xB0-0xB2 contain hash patterns that you would NOT want extended into the 9th column.
*
* The CGA font is part of the same ROM. In fact, there are TWO CGA fonts in the ROM: a thin 5x7 "single dot"
* font located at offset 0x1000, and a thick 7x7 "double dot" font at offset 0x1800. The latter is the default
@ -3550,11 +3548,11 @@ Video.prototype.createFontColor = function(font, iColor, rgbColor, nDouble, offD
for (var nRowDoubler = 0; nRowDoubler <= nDouble; nRowDoubler++) {
for (x = 0; x < cxChar; x++) {
/*
* This "bit" of logic takes care of those characters (0xB0-0xDF) whose 9th bit must mirror the 8th bit;
* This "bit" of logic takes care of those characters (0xC0-0xDF) whose 9th bit must mirror the 8th bit;
* in all other cases, any bit past the 8th bit is automatically zero. It also takes care of embedding a solid
* row of bits whenever fUnderline is true.
*/
var bit = (fUnderline? 1 : (b & (0x80 >> (x >= 8 && iChar >= 0xB0 && iChar <= 0xDF? 7 : x))));
var bit = (fUnderline? 1 : (b & (0x80 >> (x >= 8 && iChar >= 0xC0 && iChar <= 0xDF? 7 : x))));
var xDst = (x << nDouble);
var yDst = (y << nDouble) + nRowDoubler;
var rgb = (bit? rgbColor : rgbOff);