/n/dump/2010/0407/usr/cinap_lenrek/code/tuttleboot/sys/src/boot/pc/bootiso.s:120,133 - bootiso.s:120,135
  	CLR(rDX)
  	LWI(0x0010, rAX)

- 	LWI(100, rCX)
+ 	LWI(0xFF, rCX)
+ 	CLR(rBX)
  _nextpvd:
  	CALL16(BIOSread(SB))
- 	LBPB(Xbuf, rBX)
+ 	LBPB(Xbuf, rBL)
  	CMPI(1, rBX)
  	JEQ _pvdfound
+ 	CLR(rBX)
  	ADDI(1, rAX)
- 	ADC(rCX, rDX)
+ 	ADC(rBX, rDX)
  	LOOP _nextpvd

  	CALL16(srcherror(SB))
/n/dump/2010/0407/usr/cinap_lenrek/code/tuttleboot/sys/src/boot/pc/bootiso.s:158,167 - bootiso.s:160,174
  	JMP _loop

  TEXT BIOSread(SB), $0
+
  	LWI(5, rDI)			/* retry count (ATAPI ZIPs suck) */

  _retry:
  	PUSHA
+ 	PUSHS(rDS)
+ 	PUSHS(rES)
+ 	PUSHS(rFS)
+ 	PUSHS(rGS)

  	SBPW(rAX, Xdap+8)
  	SBPW(rDX, Xdap+10)
/n/dump/2010/0407/usr/cinap_lenrek/code/tuttleboot/sys/src/boot/pc/bootiso.s:170,187 - bootiso.s:177,195
  	MW(rBP, rSI)
  	ADDI(Xbuf, rSI)
  	SBPW(rSI, Xdap+4)		/* transfer buffer :offset */
- 	MFSR(rES, rSI)			/* transfer buffer seg: */
+ 	MFSR(rSS, rSI)			/* transfer buffer seg: */
  	SBPW(rSI, Xdap+6)

  	MW(rBP, rSI)			/* Xdap == BP */
  	LBPB(Xdrive, rDL)
- 	LBI(0x42, rAH)
+ 	LWI(0x4200, rAX)
+
  	BIOSCALL(0x13)
- 	JCC _popret
+ 	JCC _readok

  _reset:
  	LWI((0x0E00+'?'), rAX)
- 	BIOSCALL(0x10)
+ 	BIOSCALL(0x10)

  	/* reset the drive */
  	LBPB(Xdrive, rDL)
/n/dump/2010/0407/usr/cinap_lenrek/code/tuttleboot/sys/src/boot/pc/bootiso.s:188,194 - bootiso.s:196,207
  	CLR(rAX)
  	BIOSCALL(0x13)

+ 	POPS(rGS)
+ 	POPS(rFS)
+ 	POPS(rES)
+ 	POPS(rDS)
  	POPA
+
  	DEC(rDI)
  	JNE _retry

/n/dump/2010/0407/usr/cinap_lenrek/code/tuttleboot/sys/src/boot/pc/bootiso.s:219,226 - bootiso.s:232,244
  	POKEW				/* MOVW	AX, ES:[BX] */
  	FARJUMP16(0xFFFF, 0x0000)

- _popret:
+ _readok:
+ 	POPS(rGS)
+ 	POPS(rFS)
+ 	POPS(rES)
+ 	POPS(rDS)
  	POPA
+
  	RET

  TEXT walk(SB), $0