diff --git a/src/lib/ultra/io/gbpakcheckconnector.c b/src/lib/ultra/io/gbpakcheckconnector.c
index 9384bac22..491ecb0eb 100644
--- a/src/lib/ultra/io/gbpakcheckconnector.c
+++ b/src/lib/ultra/io/gbpakcheckconnector.c
@@ -1,328 +1,222 @@
 #include <ultra64.h>
 #include "constants.h"
 #include "bss.h"
-#include "lib/libc/ll.h"
-#include "lib/lib_4e090.h"
 #include "data.h"
 #include "types.h"
 
-GLOBAL_ASM(
-glabel osGbpakCheckConnector
-/*    50f20:	27bdfdf0 */ 	addiu	$sp,$sp,-528
-/*    50f24:	afbf0044 */ 	sw	$ra,0x44($sp)
-/*    50f28:	240e0001 */ 	addiu	$t6,$zero,0x1
-/*    50f2c:	afbe0040 */ 	sw	$s8,0x40($sp)
-/*    50f30:	afb7003c */ 	sw	$s7,0x3c($sp)
-/*    50f34:	afb60038 */ 	sw	$s6,0x38($sp)
-/*    50f38:	afb50034 */ 	sw	$s5,0x34($sp)
-/*    50f3c:	afb40030 */ 	sw	$s4,0x30($sp)
-/*    50f40:	afb3002c */ 	sw	$s3,0x2c($sp)
-/*    50f44:	afb20028 */ 	sw	$s2,0x28($sp)
-/*    50f48:	afb10024 */ 	sw	$s1,0x24($sp)
-/*    50f4c:	afb00020 */ 	sw	$s0,0x20($sp)
-/*    50f50:	afa40210 */ 	sw	$a0,0x210($sp)
-/*    50f54:	afa50214 */ 	sw	$a1,0x214($sp)
-/*    50f58:	afae0208 */ 	sw	$t6,0x208($sp)
-/*    50f5c:	afa00204 */ 	sw	$zero,0x204($sp)
-/*    50f60:	0c0142f8 */ 	jal	osGbpakGetStatus
-/*    50f64:	a7a00200 */ 	sh	$zero,0x200($sp)
-/*    50f68:	2401000d */ 	addiu	$at,$zero,0xd
-/*    50f6c:	14410005 */ 	bne	$v0,$at,.L00050f84
-/*    50f70:	00401825 */ 	or	$v1,$v0,$zero
-/*    50f74:	8fa40210 */ 	lw	$a0,0x210($sp)
-/*    50f78:	0c0142f8 */ 	jal	osGbpakGetStatus
-/*    50f7c:	8fa50214 */ 	lw	$a1,0x214($sp)
-/*    50f80:	00401825 */ 	or	$v1,$v0,$zero
-.L00050f84:
-/*    50f84:	2401000d */ 	addiu	$at,$zero,0xd
-/*    50f88:	14410003 */ 	bne	$v0,$at,.L00050f98
-/*    50f8c:	00000000 */ 	nop
-/*    50f90:	100000f9 */ 	b	.L00051378
-/*    50f94:	24020004 */ 	addiu	$v0,$zero,0x4
-.L00050f98:
-/*    50f98:	144000f6 */ 	bnez	$v0,.L00051374
-/*    50f9c:	8faf0214 */ 	lw	$t7,0x214($sp)
-/*    50fa0:	91f80000 */ 	lbu	$t8,0x0($t7)
-/*    50fa4:	8fa40210 */ 	lw	$a0,0x210($sp)
-/*    50fa8:	33190001 */ 	andi	$t9,$t8,0x1
-/*    50fac:	57200008 */ 	bnezl	$t9,.L00050fd0
-/*    50fb0:	27a40070 */ 	addiu	$a0,$sp,0x70
-/*    50fb4:	0c0018cc */ 	jal	osGbpakPower
-/*    50fb8:	24050001 */ 	addiu	$a1,$zero,0x1
-/*    50fbc:	50400004 */ 	beqzl	$v0,.L00050fd0
-/*    50fc0:	27a40070 */ 	addiu	$a0,$sp,0x70
-/*    50fc4:	100000ed */ 	b	.L0005137c
-/*    50fc8:	8fbf0044 */ 	lw	$ra,0x44($sp)
-/*    50fcc:	27a40070 */ 	addiu	$a0,$sp,0x70
-.L00050fd0:
-/*    50fd0:	0c012c30 */ 	jal	bzero
-/*    50fd4:	2405000c */ 	addiu	$a1,$zero,0xc
-/*    50fd8:	24080080 */ 	addiu	$t0,$zero,0x80
-/*    50fdc:	24020080 */ 	addiu	$v0,$zero,0x80
-/*    50fe0:	afa20068 */ 	sw	$v0,0x68($sp)
-/*    50fe4:	a7a80202 */ 	sh	$t0,0x202($sp)
-/*    50fe8:	24160001 */ 	addiu	$s6,$zero,0x1
-.L00050fec:
-/*    50fec:	8fa90208 */ 	lw	$t1,0x208($sp)
-/*    50ff0:	27ab007c */ 	addiu	$t3,$sp,0x7c
-/*    50ff4:	00009825 */ 	or	$s3,$zero,$zero
-/*    50ff8:	000951c0 */ 	sll	$t2,$t1,0x7
-/*    50ffc:	00009025 */ 	or	$s2,$zero,$zero
-/*    51000:	014bf021 */ 	addu	$s8,$t2,$t3
-.L00051004:
-/*    51004:	8fa20068 */ 	lw	$v0,0x68($sp)
-/*    51008:	00138140 */ 	sll	$s0,$s3,0x5
-/*    5100c:	03d0a821 */ 	addu	$s5,$s8,$s0
-/*    51010:	00523021 */ 	addu	$a2,$v0,$s2
-/*    51014:	30ccffff */ 	andi	$t4,$a2,0xffff
-/*    51018:	240d0020 */ 	addiu	$t5,$zero,0x20
-/*    5101c:	afad0010 */ 	sw	$t5,0x10($sp)
-/*    51020:	01803025 */ 	or	$a2,$t4,$zero
-/*    51024:	02a03825 */ 	or	$a3,$s5,$zero
-/*    51028:	8fa40210 */ 	lw	$a0,0x210($sp)
-/*    5102c:	00002825 */ 	or	$a1,$zero,$zero
-/*    51030:	0c0144ec */ 	jal	osGbpakReadWrite
-/*    51034:	0240a025 */ 	or	$s4,$s2,$zero
-/*    51038:	10400003 */ 	beqz	$v0,.L00051048
-/*    5103c:	8fae0208 */ 	lw	$t6,0x208($sp)
-/*    51040:	100000ce */ 	b	.L0005137c
-/*    51044:	8fbf0044 */ 	lw	$ra,0x44($sp)
-.L00051048:
-/*    51048:	000e7880 */ 	sll	$t7,$t6,0x2
-/*    5104c:	27b80070 */ 	addiu	$t8,$sp,0x70
-/*    51050:	01f8b821 */ 	addu	$s7,$t7,$t8
-/*    51054:	02f3c821 */ 	addu	$t9,$s7,$s3
-/*    51058:	a3360000 */ 	sb	$s6,0x0($t9)
-/*    5105c:	8fa80204 */ 	lw	$t0,0x204($sp)
-/*    51060:	27ab0070 */ 	addiu	$t3,$sp,0x70
-/*    51064:	27ad007c */ 	addiu	$t5,$sp,0x7c
-/*    51068:	00084880 */ 	sll	$t1,$t0,0x2
-/*    5106c:	01335021 */ 	addu	$t2,$t1,$s3
-/*    51070:	014b8821 */ 	addu	$s1,$t2,$t3
-/*    51074:	922e0000 */ 	lbu	$t6,0x0($s1)
-/*    51078:	000861c0 */ 	sll	$t4,$t0,0x7
-/*    5107c:	018d9021 */ 	addu	$s2,$t4,$t5
-/*    51080:	15c0000f */ 	bnez	$t6,.L000510c0
-/*    51084:	8fa40210 */ 	lw	$a0,0x210($sp)
-/*    51088:	97af0200 */ 	lhu	$t7,0x200($sp)
-/*    5108c:	24190020 */ 	addiu	$t9,$zero,0x20
-/*    51090:	afb90010 */ 	sw	$t9,0x10($sp)
-/*    51094:	01f43021 */ 	addu	$a2,$t7,$s4
-/*    51098:	30d8ffff */ 	andi	$t8,$a2,0xffff
-/*    5109c:	03003025 */ 	or	$a2,$t8,$zero
-/*    510a0:	00002825 */ 	or	$a1,$zero,$zero
-/*    510a4:	0c0144ec */ 	jal	osGbpakReadWrite
-/*    510a8:	02503821 */ 	addu	$a3,$s2,$s0
-/*    510ac:	50400004 */ 	beqzl	$v0,.L000510c0
-/*    510b0:	a2360000 */ 	sb	$s6,0x0($s1)
-/*    510b4:	100000b1 */ 	b	.L0005137c
-/*    510b8:	8fbf0044 */ 	lw	$ra,0x44($sp)
-/*    510bc:	a2360000 */ 	sb	$s6,0x0($s1)
-.L000510c0:
-/*    510c0:	02a02025 */ 	or	$a0,$s5,$zero
-/*    510c4:	02502821 */ 	addu	$a1,$s2,$s0
-/*    510c8:	0c013824 */ 	jal	bcmp
-/*    510cc:	24060020 */ 	addiu	$a2,$zero,0x20
-/*    510d0:	10400003 */ 	beqz	$v0,.L000510e0
-/*    510d4:	26920020 */ 	addiu	$s2,$s4,0x20
-/*    510d8:	10000008 */ 	b	.L000510fc
-/*    510dc:	00009825 */ 	or	$s3,$zero,$zero
-.L000510e0:
-/*    510e0:	2a620003 */ 	slti	$v0,$s3,0x3
-/*    510e4:	26730001 */ 	addiu	$s3,$s3,0x1
-/*    510e8:	326affff */ 	andi	$t2,$s3,0xffff
-/*    510ec:	3249ffff */ 	andi	$t1,$s2,0xffff
-/*    510f0:	01209025 */ 	or	$s2,$t1,$zero
-/*    510f4:	1440ffc3 */ 	bnez	$v0,.L00051004
-/*    510f8:	01409825 */ 	or	$s3,$t2,$zero
-.L000510fc:
-/*    510fc:	12600003 */ 	beqz	$s3,.L0005110c
-/*    51100:	02601025 */ 	or	$v0,$s3,$zero
-/*    51104:	1000009c */ 	b	.L00051378
-/*    51108:	24020004 */ 	addiu	$v0,$zero,0x4
-.L0005110c:
-/*    5110c:	8fab0204 */ 	lw	$t3,0x204($sp)
-/*    51110:	00009825 */ 	or	$s3,$zero,$zero
-/*    51114:	00009025 */ 	or	$s2,$zero,$zero
-/*    51118:	11600036 */ 	beqz	$t3,.L000511f4
-.L0005111c:
-/*    5111c:	02f38021 */ 	addu	$s0,$s7,$s3
-/*    51120:	92080000 */ 	lbu	$t0,0x0($s0)
-/*    51124:	8fa40210 */ 	lw	$a0,0x210($sp)
-/*    51128:	00002825 */ 	or	$a1,$zero,$zero
-/*    5112c:	1500000e */ 	bnez	$t0,.L00051168
-/*    51130:	8fac0068 */ 	lw	$t4,0x68($sp)
-/*    51134:	01923021 */ 	addu	$a2,$t4,$s2
-/*    51138:	30cdffff */ 	andi	$t5,$a2,0xffff
-/*    5113c:	00137140 */ 	sll	$t6,$s3,0x5
-/*    51140:	240f0020 */ 	addiu	$t7,$zero,0x20
-/*    51144:	afaf0010 */ 	sw	$t7,0x10($sp)
-/*    51148:	03ce3821 */ 	addu	$a3,$s8,$t6
-/*    5114c:	0c0144ec */ 	jal	osGbpakReadWrite
-/*    51150:	01a03025 */ 	or	$a2,$t5,$zero
-/*    51154:	50400004 */ 	beqzl	$v0,.L00051168
-/*    51158:	a2160000 */ 	sb	$s6,0x0($s0)
-/*    5115c:	10000087 */ 	b	.L0005137c
-/*    51160:	8fbf0044 */ 	lw	$ra,0x44($sp)
-/*    51164:	a2160000 */ 	sb	$s6,0x0($s0)
-.L00051168:
-/*    51168:	27b80070 */ 	addiu	$t8,$sp,0x70
-/*    5116c:	02788821 */ 	addu	$s1,$s3,$t8
-/*    51170:	92390000 */ 	lbu	$t9,0x0($s1)
-/*    51174:	00138140 */ 	sll	$s0,$s3,0x5
-/*    51178:	8fa40210 */ 	lw	$a0,0x210($sp)
-/*    5117c:	1720000c */ 	bnez	$t9,.L000511b0
-/*    51180:	00002825 */ 	or	$a1,$zero,$zero
-/*    51184:	27a9007c */ 	addiu	$t1,$sp,0x7c
-/*    51188:	240a0020 */ 	addiu	$t2,$zero,0x20
-/*    5118c:	afaa0010 */ 	sw	$t2,0x10($sp)
-/*    51190:	02093821 */ 	addu	$a3,$s0,$t1
-/*    51194:	0c0144ec */ 	jal	osGbpakReadWrite
-/*    51198:	3246ffff */ 	andi	$a2,$s2,0xffff
-/*    5119c:	50400004 */ 	beqzl	$v0,.L000511b0
-/*    511a0:	a2360000 */ 	sb	$s6,0x0($s1)
-/*    511a4:	10000075 */ 	b	.L0005137c
-/*    511a8:	8fbf0044 */ 	lw	$ra,0x44($sp)
-/*    511ac:	a2360000 */ 	sb	$s6,0x0($s1)
-.L000511b0:
-/*    511b0:	27ab007c */ 	addiu	$t3,$sp,0x7c
-/*    511b4:	020b2821 */ 	addu	$a1,$s0,$t3
-/*    511b8:	03d02021 */ 	addu	$a0,$s8,$s0
-/*    511bc:	0c013824 */ 	jal	bcmp
-/*    511c0:	24060020 */ 	addiu	$a2,$zero,0x20
-/*    511c4:	10400003 */ 	beqz	$v0,.L000511d4
-/*    511c8:	26520020 */ 	addiu	$s2,$s2,0x20
-/*    511cc:	10000009 */ 	b	.L000511f4
-/*    511d0:	00001025 */ 	or	$v0,$zero,$zero
-.L000511d4:
-/*    511d4:	2a620003 */ 	slti	$v0,$s3,0x3
-/*    511d8:	26730001 */ 	addiu	$s3,$s3,0x1
-/*    511dc:	326cffff */ 	andi	$t4,$s3,0xffff
-/*    511e0:	3248ffff */ 	andi	$t0,$s2,0xffff
-/*    511e4:	01009025 */ 	or	$s2,$t0,$zero
-/*    511e8:	1440ffcc */ 	bnez	$v0,.L0005111c
-/*    511ec:	01809825 */ 	or	$s3,$t4,$zero
-/*    511f0:	01801025 */ 	or	$v0,$t4,$zero
-.L000511f4:
-/*    511f4:	10400003 */ 	beqz	$v0,.L00051204
-/*    511f8:	8fad0204 */ 	lw	$t5,0x204($sp)
-/*    511fc:	1000005e */ 	b	.L00051378
-/*    51200:	24020004 */ 	addiu	$v0,$zero,0x4
-.L00051204:
-/*    51204:	11a00005 */ 	beqz	$t5,.L0005121c
-/*    51208:	000d7080 */ 	sll	$t6,$t5,0x2
-/*    5120c:	27af0070 */ 	addiu	$t7,$sp,0x70
-/*    51210:	01cf2021 */ 	addu	$a0,$t6,$t7
-/*    51214:	0c012c30 */ 	jal	bzero
-/*    51218:	24050004 */ 	addiu	$a1,$zero,0x4
-.L0005121c:
-/*    5121c:	8faa0068 */ 	lw	$t2,0x68($sp)
-/*    51220:	8fb90208 */ 	lw	$t9,0x208($sp)
-/*    51224:	97b80202 */ 	lhu	$t8,0x202($sp)
-/*    51228:	000a5840 */ 	sll	$t3,$t2,0x1
-/*    5122c:	3168ffff */ 	andi	$t0,$t3,0xffff
-/*    51230:	29014001 */ 	slti	$at,$t0,0x4001
-/*    51234:	3b290003 */ 	xori	$t1,$t9,0x3
-/*    51238:	afa80068 */ 	sw	$t0,0x68($sp)
-/*    5123c:	a7ab0202 */ 	sh	$t3,0x202($sp)
-/*    51240:	afa90208 */ 	sw	$t1,0x208($sp)
-/*    51244:	afb90204 */ 	sw	$t9,0x204($sp)
-/*    51248:	1420ff68 */ 	bnez	$at,.L00050fec
-/*    5124c:	a7b80200 */ 	sh	$t8,0x200($sp)
-/*    51250:	8fac0210 */ 	lw	$t4,0x210($sp)
-/*    51254:	8faf0208 */ 	lw	$t7,0x208($sp)
-/*    51258:	00009825 */ 	or	$s3,$zero,$zero
-/*    5125c:	8d8d0050 */ 	lw	$t5,0x50($t4)
-/*    51260:	00009025 */ 	or	$s2,$zero,$zero
-/*    51264:	27b9007c */ 	addiu	$t9,$sp,0x7c
-/*    51268:	29a10002 */ 	slti	$at,$t5,0x2
-/*    5126c:	10200005 */ 	beqz	$at,.L00051284
-/*    51270:	000fc1c0 */ 	sll	$t8,$t7,0x7
-/*    51274:	8d8e004c */ 	lw	$t6,0x4c($t4)
-/*    51278:	24010002 */ 	addiu	$at,$zero,0x2
-/*    5127c:	55c10037 */ 	bnel	$t6,$at,.L0005135c
-/*    51280:	8fa40210 */ 	lw	$a0,0x210($sp)
-.L00051284:
-/*    51284:	0319f021 */ 	addu	$s8,$t8,$t9
-/*    51288:	3416a000 */ 	dli	$s6,0xa000
-.L0005128c:
-/*    5128c:	02563021 */ 	addu	$a2,$s2,$s6
-/*    51290:	00138140 */ 	sll	$s0,$s3,0x5
-/*    51294:	03d0a821 */ 	addu	$s5,$s8,$s0
-/*    51298:	30c9ffff */ 	andi	$t1,$a2,0xffff
-/*    5129c:	240a0020 */ 	addiu	$t2,$zero,0x20
-/*    512a0:	afaa0010 */ 	sw	$t2,0x10($sp)
-/*    512a4:	01203025 */ 	or	$a2,$t1,$zero
-/*    512a8:	02a03825 */ 	or	$a3,$s5,$zero
-/*    512ac:	8fa40210 */ 	lw	$a0,0x210($sp)
-/*    512b0:	00002825 */ 	or	$a1,$zero,$zero
-/*    512b4:	0c0144ec */ 	jal	osGbpakReadWrite
-/*    512b8:	0240a025 */ 	or	$s4,$s2,$zero
-/*    512bc:	10400003 */ 	beqz	$v0,.L000512cc
-/*    512c0:	8fa40210 */ 	lw	$a0,0x210($sp)
-/*    512c4:	1000002d */ 	b	.L0005137c
-/*    512c8:	8fbf0044 */ 	lw	$ra,0x44($sp)
-.L000512cc:
-/*    512cc:	8fa80204 */ 	lw	$t0,0x204($sp)
-/*    512d0:	26862000 */ 	addiu	$a2,$s4,0x2000
-/*    512d4:	27ae007c */ 	addiu	$t6,$sp,0x7c
-/*    512d8:	000869c0 */ 	sll	$t5,$t0,0x7
-/*    512dc:	01b06021 */ 	addu	$t4,$t5,$s0
-/*    512e0:	018e8821 */ 	addu	$s1,$t4,$t6
-/*    512e4:	30cbffff */ 	andi	$t3,$a2,0xffff
-/*    512e8:	240f0020 */ 	addiu	$t7,$zero,0x20
-/*    512ec:	afaf0010 */ 	sw	$t7,0x10($sp)
-/*    512f0:	01603025 */ 	or	$a2,$t3,$zero
-/*    512f4:	02203825 */ 	or	$a3,$s1,$zero
-/*    512f8:	0c0144ec */ 	jal	osGbpakReadWrite
-/*    512fc:	00002825 */ 	or	$a1,$zero,$zero
-/*    51300:	10400003 */ 	beqz	$v0,.L00051310
-/*    51304:	02a02025 */ 	or	$a0,$s5,$zero
-/*    51308:	1000001c */ 	b	.L0005137c
-/*    5130c:	8fbf0044 */ 	lw	$ra,0x44($sp)
-.L00051310:
-/*    51310:	02202825 */ 	or	$a1,$s1,$zero
-/*    51314:	0c013824 */ 	jal	bcmp
-/*    51318:	24060020 */ 	addiu	$a2,$zero,0x20
-/*    5131c:	10400003 */ 	beqz	$v0,.L0005132c
-/*    51320:	26920020 */ 	addiu	$s2,$s4,0x20
-/*    51324:	10000008 */ 	b	.L00051348
-/*    51328:	00009825 */ 	or	$s3,$zero,$zero
-.L0005132c:
-/*    5132c:	2a620003 */ 	slti	$v0,$s3,0x3
-/*    51330:	26730001 */ 	addiu	$s3,$s3,0x1
-/*    51334:	3279ffff */ 	andi	$t9,$s3,0xffff
-/*    51338:	3258ffff */ 	andi	$t8,$s2,0xffff
-/*    5133c:	03009025 */ 	or	$s2,$t8,$zero
-/*    51340:	1440ffd2 */ 	bnez	$v0,.L0005128c
-/*    51344:	03209825 */ 	or	$s3,$t9,$zero
-.L00051348:
-/*    51348:	52600004 */ 	beqzl	$s3,.L0005135c
-/*    5134c:	8fa40210 */ 	lw	$a0,0x210($sp)
-/*    51350:	10000009 */ 	b	.L00051378
-/*    51354:	24020004 */ 	addiu	$v0,$zero,0x4
-/*    51358:	8fa40210 */ 	lw	$a0,0x210($sp)
-.L0005135c:
-/*    5135c:	0c0142f8 */ 	jal	osGbpakGetStatus
-/*    51360:	8fa50214 */ 	lw	$a1,0x214($sp)
-/*    51364:	2401000d */ 	addiu	$at,$zero,0xd
-/*    51368:	14410002 */ 	bne	$v0,$at,.L00051374
-/*    5136c:	00401825 */ 	or	$v1,$v0,$zero
-/*    51370:	24030004 */ 	addiu	$v1,$zero,0x4
-.L00051374:
-/*    51374:	00601025 */ 	or	$v0,$v1,$zero
-.L00051378:
-/*    51378:	8fbf0044 */ 	lw	$ra,0x44($sp)
-.L0005137c:
-/*    5137c:	8fb00020 */ 	lw	$s0,0x20($sp)
-/*    51380:	8fb10024 */ 	lw	$s1,0x24($sp)
-/*    51384:	8fb20028 */ 	lw	$s2,0x28($sp)
-/*    51388:	8fb3002c */ 	lw	$s3,0x2c($sp)
-/*    5138c:	8fb40030 */ 	lw	$s4,0x30($sp)
-/*    51390:	8fb50034 */ 	lw	$s5,0x34($sp)
-/*    51394:	8fb60038 */ 	lw	$s6,0x38($sp)
-/*    51398:	8fb7003c */ 	lw	$s7,0x3c($sp)
-/*    5139c:	8fbe0040 */ 	lw	$s8,0x40($sp)
-/*    513a0:	03e00008 */ 	jr	$ra
-/*    513a4:	27bd0210 */ 	addiu	$sp,$sp,0x210
-);
+/**
+ * The internal operations performed by the osGbpakCheckConnector function are
+ * as follows.
+ *
+ * - Checks the ROM area addresses of the Game Boy Game Pak and performs the
+ *   following processing for 0x0000, 0x0080, 0x0100, 0x0200, 0x0400, 0x0800,
+ *   0x1000, 0x2000, and 0x4000.
+ *
+ *   1. Compares data starting at the above addresses with neighboring data in
+ *      32-byte units.
+ *   2. If the data are identical, compares the next 32 bytes, and if this is
+ *      also the same, compares the next 32 bytes. Up to 4 comparisons (ie, 128
+ *      bytes) are performed. If all data are identical, the address line is
+ *      considered insecurely connected and an error is returned. If different
+ *      data are detected even once, it is determined that the data are being
+ *      read properly and the function advances.
+ *   3. Data at each of the above addresses are compared with the data starting
+ *      at 0x0000 in 32-byte units.
+ *   4. As in 2., up to 4 comparisons (128 bytes) are made. If all the data are
+ *      identical, an error is returned. If different data are detected even
+ *      once, it is determined that the data are being read properly and the
+ *      function advances.
+ *
+ * - If a RAM area exists, the function checks the address of the Game Boy Game
+ *   Pak RAM area and performs the following processing for 0x2000 and 0xa000.
+ *
+ *   1. Compares the data starting at the above addresses in 32-byte units.
+ *   2. If the data are identical, compares the next 32 bytes, and if this is
+ *      also the same, compares the next 32 bytes. Up to 4 comparisons (ie, 128
+ *      bytes) are performed. If all the data are the same, the address line is
+ *      evaluated to be insecurely connected and an error is returned. If
+ *      different data are detected even once, it is determined that the data
+ *      are being read properly and the function advances.
+ */
+s32 osGbpakCheckConnector(OSPfs *pfs, u8 *status)
+{
+	s32 ret;
+	s32 thisslot = 1;
+	s32 prevslot = 0;
+	u16 thischunkaddr;
+	u16 prevchunkaddr = 0;
+	u16 offset;
+	u16 blocknum;
+	u8 blocks[3][4][0x20];
+	u8 blocksloaded[3][4];
+	bool stilllooking;
+
+	ret = osGbpakGetStatus(pfs, status);
+
+	if (ret == PFS_ERR_NEW_GBCART) {
+		ret = osGbpakGetStatus(pfs, status);
+	}
+
+	if (ret == PFS_ERR_NEW_GBCART) {
+		return PFS_ERR_CONTRFAIL;
+	}
+
+	if (ret == 0) {
+		if ((*status & OS_GBPAK_POWER) == 0) {
+			ret = osGbpakPower(pfs, OS_GBPAK_POWER_ON);
+
+			if (ret != 0) {
+				return ret;
+			}
+		}
+
+		bzero(blocksloaded, 12);
+
+		for (thischunkaddr = 0x80; thischunkaddr <= 0x4000; thischunkaddr *= 2) {
+			blocknum = 0;
+			offset = 0;
+
+			do {
+				// Load the current block
+				ret = osGbpakReadWrite(pfs, PFS_READ, thischunkaddr + offset, blocks[thisslot][blocknum], 32);
+
+				if (ret != 0) {
+					return ret;
+				}
+
+				blocksloaded[thisslot][blocknum] = 1;
+
+				// Load the same block from the previous chunk if not already loaded
+				// (This only applies for the 0x0000 chunk)
+				if (blocksloaded[prevslot][blocknum] == 0) {
+					ret = osGbpakReadWrite(pfs, PFS_READ, prevchunkaddr + offset, blocks[prevslot][blocknum], 32);
+
+					if (ret != 0) {
+						return ret;
+					}
+
+					blocksloaded[prevslot][blocknum] = 1;
+				}
+
+				// Compare them and bail out if different
+				if (bcmp(blocks[thisslot][blocknum], blocks[prevslot][blocknum], 32) != 0) {
+					blocknum = 0;
+					break;
+				}
+
+				stilllooking = blocknum < 3;
+				offset += 0x20; blocknum++;
+			} while (stilllooking);
+
+			if (blocknum);
+			if (blocknum);
+			if (blocknum);
+			if (blocknum);
+			if (blocknum);
+			if (blocknum);
+
+			stilllooking = blocknum;
+
+			if (stilllooking) {
+				return PFS_ERR_CONTRFAIL;
+			}
+
+			// Now compare each block in this chunk with each block in the
+			// 0x0000 chunk
+			blocknum = 0;
+			offset = 0;
+
+			if (prevslot != 0) {
+				do {
+					// Make sure the current block is loaded
+					if (blocksloaded[thisslot][blocknum] == 0) {
+						ret = osGbpakReadWrite(pfs, PFS_READ, thischunkaddr + offset, blocks[thisslot][blocknum], 32);
+
+						if (ret != 0) {
+							return ret;
+						}
+
+						blocksloaded[thisslot][blocknum] = 1;
+					}
+
+					// Make sure this block in chunk 0x0000 is loaded
+					if (blocksloaded[0][blocknum] == 0) {
+						ret = osGbpakReadWrite(pfs, PFS_READ, offset, blocks[0][blocknum], 32);
+
+						if (ret != 0) {
+							return ret;
+						}
+
+						blocksloaded[0][blocknum] = 1;
+					}
+
+					// Compare them and bail out if different
+					if (bcmp(blocks[thisslot][blocknum], blocks[0][blocknum], 32) != 0) {
+						stilllooking = false;
+						goto foo;
+					}
+
+					stilllooking = blocknum < 3;
+					offset += 0x20; blocknum++;
+				} while (stilllooking);
+
+				stilllooking = blocknum;
+			}
+
+foo:
+			if (stilllooking) {
+				return PFS_ERR_CONTRFAIL;
+			}
+
+			if (prevslot != 0) {
+				bzero(&blocksloaded[prevslot][0], 4);
+			}
+
+			prevchunkaddr = thischunkaddr;
+			prevslot = thisslot;
+			thisslot ^= 3; // toggle between 1 and 2
+		}
+
+		// Check RAM if present
+		if (pfs->dir_size >= 2 || pfs->version == 2) {
+			blocknum = 0;
+			offset = 0;
+
+			do {
+				ret = osGbpakReadWrite(pfs, PFS_READ, 0xa000 + offset, blocks[thisslot][blocknum], 32);
+
+				if (ret != 0) {
+					return ret;
+				}
+
+				ret = osGbpakReadWrite(pfs, PFS_READ, 0x2000 + offset, blocks[prevslot][blocknum], 32);
+
+				if (ret != 0) {
+					return ret;
+				}
+
+				if (bcmp(blocks[thisslot][blocknum], blocks[prevslot][blocknum], 32) != 0) {
+					blocknum = 0;
+					break;
+				}
+
+				stilllooking = blocknum < 3;
+				offset += 0x20; blocknum++;
+			} while (stilllooking);
+
+			stilllooking = blocknum;
+
+			if (stilllooking) {
+				return PFS_ERR_CONTRFAIL;
+			}
+		}
+
+		ret = osGbpakGetStatus(pfs, status);
+
+		if (ret == PFS_ERR_NEW_GBCART) {
+			ret = PFS_ERR_CONTRFAIL;
+		}
+	}
+
+	return ret;
+}