Document link patch lists a little bit better

constants/serial_constants.asm

@@ -19,8 +19,10 @@ DEF USING_EXTERNAL_CLOCK       EQU $01
 DEF USING_INTERNAL_CLOCK       EQU $02
 DEF CONNECTION_NOT_ESTABLISHED EQU $ff
 
-; length of a patch list (less than any of the signal bytes)
-DEF SERIAL_PATCH_LIST_LENGTH          EQU $fc
+; length of a patch list
+DEF SERIAL_PATCH_LIST_LENGTH          EQU 200
+; size of the patch area (offsets into this area may not have special values)
+DEF SERIAL_PATCH_DATA_SIZE            EQU $fc
 ; signals the start of an array of bytes transferred over the link cable
 DEF SERIAL_PREAMBLE_BYTE              EQU $fd
 ; this byte is used when there is no data to send

engine/link/link.asm

@@ -98,7 +98,7 @@ endc
 
 	ld hl, wPlayerPatchLists
 	ld de, wOTPatchLists
-	ld bc, 200
+	ld bc, SERIAL_PATCH_LIST_LENGTH
 	vc_hook Wireless_ExchangeBytes_Gen2toGen1_patch_lists
 	call Serial_ExchangeBytes
 
@@ -126,7 +126,7 @@ endc
 	call Link_CopyOTData
 
 	ld de, wOTPatchLists
-	ld hl, wLinkPatchList1
+	ld hl, wLinkPatchData1
 	ld c, 2
 .loop
 	ld a, [de]
@@ -152,7 +152,7 @@ endc
 	jr .loop
 
 .next
-	ld hl, wLinkPatchList2
+	ld hl, wLinkPatchData2
 	dec c
 	jr nz, .loop
 
@@ -264,7 +264,7 @@ endc
 
 	ld hl, wPlayerPatchLists
 	ld de, wOTPatchLists
-	ld bc, 200
+	ld bc, SERIAL_PATCH_LIST_LENGTH
 	vc_hook Wireless_ExchangeBytes_patch_lists
 	call Serial_ExchangeBytes
 
@@ -294,7 +294,7 @@ endc
 	call Link_CopyOTData
 
 	ld de, wPlayerTrademon
-	ld hl, wLinkPatchList1
+	ld hl, wLinkPatchData1
 	ld c, 2
 .loop1
 	ld a, [de]
@@ -320,7 +320,7 @@ endc
 	jr .loop1
 
 .next1
-	ld hl, wLinkPatchList2
+	ld hl, wLinkPatchData2
 	dec c
 	jr nz, .loop1
 
@@ -615,6 +615,7 @@ FixDataForLinkTransfer:
 	dec b
 	jr nz, .preamble_loop
 
+; Initialize random seed, making sure special bytes are omitted
 	assert wLinkBattleRNPreamble + SERIAL_RN_PREAMBLE_LENGTH == wLinkBattleRNs
 	ld b, SERIAL_RNS_LENGTH
 .rn_loop
@@ -625,60 +626,66 @@ FixDataForLinkTransfer:
 	dec b
 	jr nz, .rn_loop
 
+; Clear the patch list
 	ld hl, wPlayerPatchLists
 	ld a, SERIAL_PREAMBLE_BYTE
 	ld [hli], a
 	ld [hli], a
 	ld [hli], a
-
-	ld b, 200
+	ld b, SERIAL_PATCH_LIST_LENGTH
 	xor a
-.loop1
+.clear_loop
 	ld [hli], a
 	dec b
-	jr nz, .loop1
+	jr nz, .clear_loop
 
-	ld hl, (wLinkData + SERIAL_PREAMBLE_LENGTH + NAME_LENGTH + 1 + PARTY_LENGTH + 1) - 1
-	ld de, wPlayerPatchLists + 10 ; ???
+; Loop through all the patchable link data
+	ld hl, wLinkData + SERIAL_PREAMBLE_LENGTH + NAME_LENGTH + (1 + PARTY_LENGTH + 1) - 1
+	ld de, wPlayerPatchLists + SERIAL_RNS_LENGTH ; ???
 	lb bc, 0, 0
-.loop2
+.patch_loop
+; Check if we've gone over the entire area
 	inc c
 	ld a, c
-	cp SERIAL_PATCH_LIST_LENGTH + 1
-	jr z, .next1
+	cp SERIAL_PATCH_DATA_SIZE + 1
+	jr z, .data1_done
+
+; If we're processing the second patch area, check if we've reached the end
 	ld a, b
 	dec a
-	jr nz, .next2
+	jr nz, .process
 	push bc
 	ld a, [wLinkMode]
 	cp LINK_TIMECAPSULE
-	ld b, REDMON_STRUCT_LENGTH * PARTY_LENGTH - SERIAL_PATCH_LIST_LENGTH + 1
-	jr z, .got_value
-	ld b, 2 + PARTYMON_STRUCT_LENGTH * PARTY_LENGTH - SERIAL_PATCH_LIST_LENGTH + 1
-.got_value
+	ld b, REDMON_STRUCT_LENGTH * PARTY_LENGTH - SERIAL_PATCH_DATA_SIZE + 1
+	jr z, .got_size
+	ld b, 2 + PARTYMON_STRUCT_LENGTH * PARTY_LENGTH - SERIAL_PATCH_DATA_SIZE + 1
+.got_size
 	ld a, c
 	cp b
 	pop bc
-	jr z, .done
-.next2
+	jr z, .data2_done
+
+.process
+; Replace the "no data" byte, and record it in the array
 	inc hl
 	ld a, [hl]
 	cp SERIAL_NO_DATA_BYTE
-	jr nz, .loop2
+	jr nz, .patch_loop
 	ld a, c
 	ld [de], a
 	inc de
 	ld [hl], SERIAL_PATCH_REPLACEMENT_BYTE
-	jr .loop2
+	jr .patch_loop
 
-.next1
+.data1_done
 	ld a, SERIAL_PATCH_LIST_PART_TERMINATOR
 	ld [de], a
 	inc de
 	lb bc, 1, 0
-	jr .loop2
+	jr .patch_loop
 
-.done
+.data2_done
 	ld a, SERIAL_PATCH_LIST_PART_TERMINATOR
 	ld [de], a
 	ret
@@ -994,7 +1001,6 @@ Link_PrepPartyData_Gen2:
 	inc hl
 	dec b
 	jr nz, .loop6
-
 	ld a, SERIAL_PATCH_LIST_PART_TERMINATOR
 	ld [de], a
 	ret

ram/wram.asm

@@ -617,8 +617,8 @@ wBattleEnd::
 SECTION UNION "Miscellaneous", WRAM0
 
 ; link patch lists
-wPlayerPatchLists:: ds 200
-wOTPatchLists:: ds 200
+wPlayerPatchLists:: ds SERIAL_PATCH_LIST_LENGTH
+wOTPatchLists:: ds SERIAL_PATCH_LIST_LENGTH
 
 
 SECTION UNION "Miscellaneous", WRAM0
@@ -1008,8 +1008,8 @@ endr
 
 NEXTU
 ; link patch lists
-wLinkPatchList1:: ds SERIAL_PATCH_LIST_LENGTH
-wLinkPatchList2:: ds SERIAL_PATCH_LIST_LENGTH
+wLinkPatchData1:: ds SERIAL_PATCH_DATA_SIZE
+wLinkPatchData2:: ds SERIAL_PATCH_DATA_SIZE
 ENDU