Files
RFS/asm/rfs_bank10.asm
2026-04-01 23:29:33 +01:00

159 lines
8.3 KiB
NASM

;--------------------------------------------------------------------------------------------------------
;-
;- Name: rfs_bank10.asm
;- Created: July 2019
;- Author(s): Philip Smart
;- Description: Sharp MZ series Rom Filing System.
;- This assembly language program is written to utilise the banked flashroms added with
;- the MZ-80A RFS hardware upgrade.
;-
;- Credits:
;- Copyright: (c) 2018-2026 Philip Smart <philip.smart@net2net.org>
;-
;- History: July 2019 - Merged 2 utilities to create this compilation.
;- May 2020 - Bank switch changes with release of v2 pcb with coded latch. The coded
;- latch adds additional instruction overhead as the control latches share
;- the same address space as the Flash RAMS thus the extra hardware to
;- only enable the control registers if a fixed number of reads is made
;- into the upper 8 bytes which normally wouldnt occur. Caveat - ensure
;- that no loop instruction is ever placed into EFF8H - EFFFH.
;- Aug 2023 - Updates to make RFS run under the SFD700 Floppy Disk Interface board.
;- UROM remains the same, a 2K paged ROM, MROM is located at F000 when
;- RFS is built for the SFD700.
;-
;--------------------------------------------------------------------------------------------------------
;- This source file is free software: you can redistribute it and-or modify
;- it under the terms of the GNU General Public License as published
;- by the Free Software Foundation, either version 3 of the License, or
;- (at your option) any later version.
;-
;- This source 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
;- GNU General Public License for more details.
;-
;- You should have received a copy of the GNU General Public License
;- along with this program. If not, see <http://www.gnu.org/licenses/>.
;--------------------------------------------------------------------------------------------------------
IF BUILD_SFD700 = 1
ORG 0E000H
ALIGN 0E300H
DB "BANK10"
ALIGN UROMADDR
ENDIF
;===========================================================
;
; USER ROM BANK 10 -
;
;===========================================================
ORG UROMADDR
;--------------------------------
; Common code spanning all banks.
;--------------------------------
NOP
HWSELROM2 ; Select the first ROM page.
;
; No mans land... this should have switched to Bank 0 and at this point there is a jump to 00000H.
JP 00000H ; This is for safety!!
;------------------------------------------------------------------------------------------
; Bank switching code, allows a call to code in another bank.
; This code is duplicated in each bank such that a bank switch doesnt affect logic flow.
;------------------------------------------------------------------------------------------
ALIGN_NOPS UROMBSTBL
;
BKSW10to0: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK0 ; Required bank to call.
JR BKSW10_0
BKSW10to1: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK1 ; Required bank to call.
JR BKSW10_0
BKSW10to2: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK2 ; Required bank to call.
JR BKSW10_0
BKSW10to3: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK3 ; Required bank to call.
JR BKSW10_0
BKSW10to4: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK4 ; Required bank to call.
JR BKSW10_0
BKSW10to5: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK5 ; Required bank to call.
JR BKSW10_0
BKSW10to6: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK6 ; Required bank to call.
JR BKSW10_0
BKSW10to7: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK7 ; Required bank to call.
JR BKSW10_0
BKSW10to8: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK8 ; Required bank to call.
JR BKSW10_0
BKSW10to9: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK9 ; Required bank to call.
JR BKSW10_0
BKSW10to10: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK10 ; Required bank to call.
JR BKSW10_0
BKSW10to11: PUSH AF
LD A, ROMBANK10 ; Calling bank (ie. us).
PUSH AF
LD A, ROMBANK11 ; Required bank to call.
;
BKSW10_0: PUSH HL ; Place function to call on stack
LD HL, BKSWRET10 ; Place bank switchers return address on stack.
EX (SP),HL
LD (TMPSTACKP),SP ; Save the stack pointer as some old code corrupts it.
BNKSWSEL
JP (HL) ; Jump to required function.
BKSWRET10: POP AF ; Get bank which called us.
BNKSWSELRET
POP AF
RET
;-------------------------------------------------------------------------------
; START OF METHODS
;-------------------------------------------------------------------------------
;-------------------------------------------------------------------------------
; END OF METHODS
;-------------------------------------------------------------------------------
; RomDisk - Pad to EFFF boundary.
IF BUILD_ROMDISK+BUILD_PICOZ80 = 1
ALIGN 0EFF8h
ORG 0EFF8h
DB 0FFh,0FFh,0FFh,0FFh,0FFh,0FFh,0FFh,0FFh
ENDIF
; SFD700 - Pad to 10000H
IF BUILD_SFD700 = 1
ALIGN 10000H
ENDIF