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Commit 220 emulator version 0.3a:

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1. Commit initial (incomplete) implementation of magnetic tape drives (TSU) and control: MLS, MRW, MDA, MIW, MIR, MPF, MPB, MPE, MIB, MIE.
2. Change B220SetCallback.js "setImmediate" mechanism to use DOM Promises instead of window.postMessage().
3. Minor styling and window positioning changes.
This commit is contained in:
Paul Kimpel
2017-10-19 09:18:48 -07:00
parent c465da8eef
commit d518d6e044
24 changed files with 3496 additions and 245 deletions
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33
webUI/B220SetCallback.js
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@@ -18,8 +18,8 @@
* minimum they use, and their precision in activating the call-back function
* once the actual delay is established varies even more. This module will use
* setTimeout() if the requested delay time is above a certain threshold, and
* a setImmediate-like mechanism (based on window.postMessage) if the requested
* delay is below that threshold.
* a setImmediate-like mechanism (based on Promise) if the requested delay is
* below that threshold.
*
* To help compensate for the fact that the call-back function may be called
* sooner than requested, and that due either to other activity or to browser
@@ -43,9 +43,9 @@
* earlier or later than the specified delay. The string "category" (which
* may be empty, null, or undefined) defines the category under which the
* average delay difference will be maintained. setCallBack returns a
* numeric token identifying the call-back event, which can be used
* with clearCallback(). Note that passing a string in lieu of a function
* object is not permitted.
* numeric token identifying the call-back event, which can be used with
* clearCallback() to cancel the callback. Note that passing a string in
* lieu of a function object is not permitted.
*
* clearCallBack(token)
*
@@ -77,6 +77,8 @@
* Original version, cloned from retro-205 emulator D205SetCallback.js.
* 2017-02-18 P.Kimpel
* Redesign yet again the delay adjustment mechanism -- from 205 project.
* 2017-10-16 P.Kimpel
* Replace window.postMessage yield mechanism with one based on Promise().
***********************************************************************/
"use strict";
@@ -89,7 +91,6 @@
var perf = global.performance; // cached window.performance object
var pool = []; // pool of reusable callback objects
var poolLength = 0; // length of active entries in pool
var secretPrefix = "retro-205.webUI." + Date.now().toString(16);
/**************************************/
function activateCallback(token) {
@@ -140,7 +141,7 @@
/* Sets up and schedules a callback for function "fcn", called with context
"context", after a delay of "delay" ms. An optional "arg" value will be passed
to "fcn". If the delay is less than "minTimeout", a setImmediate-like mechanism
based on window.postsMessage() will be used; otherwise the environment's standard
based on DOM Promise() will be used; otherwise the environment's standard
setTimeout mechanism will be used */
var adj = 0; // adjustment to delay and delayDev[]
var categoryName = (category || "NUL").toString();
@@ -213,25 +214,12 @@
thisCallback.cancelToken = global.setTimeout(activateCallback, delay, token);
} else {
thisCallback.cancelToken = 0;
global.postMessage(secretPrefix + tokenName, "*");
Promise.resolve(token).then(activateCallback);
}
return token;
}
/**************************************/
function onMessage(ev) {
/* Handler for the global.onmessage event. Activates the callback */
var payload;
if (ev.source === global) {
payload = ev.data.toString();
if (payload.substring(0, secretPrefix.length) === secretPrefix) {
activateCallback(payload.substring(secretPrefix.length));
}
}
}
/**************************************/
function getCallbackState(optionMask) {
/* Diagnostic function. Returns an object that, depending upon bits in
@@ -270,7 +258,7 @@
}
/********** Outer block of anonymous closure **********/
if (!global.setCallback && global.postMessage && !global.importScripts) {
if (!global.setCallback && !global.importScripts) {
// Attach to the prototype of global, if possible, otherwise to global itself
var attachee = global;
@@ -282,7 +270,6 @@
}
*****/
global.addEventListener("message", onMessage, false);
attachee.setCallback = setCallback;
attachee.clearCallback = clearCallback;
attachee.getCallbackState = getCallbackState;