minivmac4ios/Mini vMac/mnvm_core/ADBEMDEV.c

/*
	ADBEMDEV.c

	Copyright (C) 2008 Paul C. Pratt

	You can redistribute this file and/or modify it under the terms
	of version 2 of the GNU General Public License as published by
	the Free Software Foundation.  You should have received a copy
	of the license along with this file; see the file COPYING.

	This file is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	license for more details.
*/

/*
	Apple Desktop Bus EMulated DEVice
*/

#ifndef AllFiles
#include "SYSDEPNS.h"
#include "MYOSGLUE.h"
#include "EMCONFIG.h"
#include "GLOBGLUE.h"
#endif

#include "ADBEMDEV.h"

#ifdef _VIA_Debug
#include <stdio.h>
#endif

/*
	ReportAbnormalID unused 0x0C06 - 0x0CFF
*/

IMPORTPROC ADB_ShiftOutData(ui3b v);
IMPORTFUNC ui3b ADB_ShiftInData(void);

#include "ADBSHARE.h"

LOCALVAR blnr ADB_ListenDatBuf;
LOCALVAR ui3b ADB_IndexDatBuf;

GLOBALPROC ADB_DoNewState(void)
{
	ui3b state = ADB_st1 * 2 + ADB_st0;
#ifdef _VIA_Debug
	fprintf(stderr, "ADB_DoNewState: %d\n", state);
#endif
	{
		ADB_Int = 1;
		switch (state) {
			case 0: /* Start a new command */
				if (ADB_ListenDatBuf) {
					ADB_ListenDatBuf = falseblnr;
					ADB_SzDatBuf = ADB_IndexDatBuf;
					ADB_EndListen();
				}
				ADB_TalkDatBuf = falseblnr;
				ADB_IndexDatBuf = 0;
				ADB_CurCmd = ADB_ShiftInData();
					/* which sets interrupt, acknowleding command */
#ifdef _VIA_Debug
				fprintf(stderr, "in: %d\n", ADB_CurCmd);
#endif
				switch ((ADB_CurCmd >> 2) & 3) {
					case 0: /* reserved */
						switch (ADB_CurCmd & 3) {
							case 0: /* Send Reset */
								ADB_DoReset();
								break;
							case 1: /* Flush */
								ADB_Flush();
								break;
							case 2: /* reserved */
							case 3: /* reserved */
								ReportAbnormalID(0x0C01,
									"Reserved ADB command");
								break;
						}
						break;
					case 1: /* reserved */
						ReportAbnormalID(0x0C02,
							"Reserved ADB command");
						break;
					case 2: /* listen */
						ADB_ListenDatBuf = trueblnr;
#ifdef _VIA_Debug
						fprintf(stderr, "*** listening\n");
#endif
						break;
					case 3: /* talk */
						ADB_DoTalk();
						break;
				}
				break;
			case 1: /* Transfer date byte (even) */
			case 2: /* Transfer date byte (odd) */
				if (! ADB_ListenDatBuf) {
					/*
						will get here even if no pending talk data,
						when there is pending event from device
						other than the one polled by the last talk
						command. this probably indicates a bug.
					*/
					if ((! ADB_TalkDatBuf)
						|| (ADB_IndexDatBuf >= ADB_SzDatBuf))
					{
						ADB_ShiftOutData(0xFF);
						ADB_Data = 1;
						ADB_Int = 0;
					} else {
#ifdef _VIA_Debug
						fprintf(stderr, "*** talk one\n");
#endif
						ADB_ShiftOutData(ADB_DatBuf[ADB_IndexDatBuf]);
						ADB_Data = 1;
						ADB_IndexDatBuf += 1;
					}
				} else {
					if (ADB_IndexDatBuf >= ADB_MaxSzDatBuf) {
						ReportAbnormalID(0x0C03, "ADB listen too much");
							/* ADB_MaxSzDatBuf isn't big enough */
						(void) ADB_ShiftInData();
					} else {
#ifdef _VIA_Debug
						fprintf(stderr, "*** listen one\n");
#endif
						ADB_DatBuf[ADB_IndexDatBuf] = ADB_ShiftInData();
						ADB_IndexDatBuf += 1;
					}
				}
				break;
			case 3: /* idle */
				if (ADB_ListenDatBuf) {
					ReportAbnormalID(0x0C04, "ADB idle follows listen");
					/* apparently doesn't happen */
				}
				if (ADB_TalkDatBuf) {
					if (ADB_IndexDatBuf != 0) {
						ReportAbnormalID(0x0C05,
							"idle when not done talking");
					}
					ADB_ShiftOutData(0xFF);
					/* ADB_Int = 0; */
				} else if (CheckForADBanyEvt()) {
					if (((ADB_CurCmd >> 2) & 3) == 3) {
						ADB_DoTalk();
					}
					ADB_ShiftOutData(0xFF);
					/* ADB_Int = 0; */
				}
				break;
		}
	}
}

GLOBALPROC ADBstate_ChangeNtfy(void)
{
#ifdef _VIA_Debug
	fprintf(stderr, "ADBstate_ChangeNtfy: %d, %d, %d\n",
		ADB_st1, ADB_st0, GetCuriCount());
#endif
	ICT_add(kICT_ADB_NewState,
		348160UL * kCycleScale / 64 * kMyClockMult);
		/*
			Macintosh Family Hardware Reference say device "must res