added BIOS skeleton

2020-12-20 20:54:09 +01:00
1 parent 5679184d50
commit c1b264ef9a
@@ -3,4 +3,177 @@
 ; Z80 Virtual Machine BIOS for CP/M
 ;

-; XXX implement
+
+; Virtual BIOS memory map
+
+; $FE00 - $FE63 - jumptable, 3*33 bytes
+; $FE63 - $FE84 - magic HALT instructions to select BIOS routines
+; $FE85 - $FEFF - unused
+; $FF00 - $FFFF - Disk Drive Tables, dynamically generated, $10 bytes for each one
+
+
+
+
+zvm_BIOS_vectable:
+
+	!word zvm_BIOS_00_BOOT
+	!word zvm_BIOS_01_WBOOT
+	!word zvm_BIOS_02_CONST
+	!word zvm_BIOS_03_CONIN
+	!word zvm_BIOS_04_CONOUT
+	!word zvm_BIOS_05_LIST
+	!word zvm_BIOS_06_AUXOUT
+	!word zvm_BIOS_07_AUXIN
+	!word zvm_BIOS_08_HOME
+	!word zvm_BIOS_09_SELDSK
+	!word zvm_BIOS_10_SETTRK
+	!word zvm_BIOS_11_SETSEC
+	!word zvm_BIOS_12_SETDMA
+	!word zvm_BIOS_13_READ
+	!word zvm_BIOS_14_WRITE
+	!word zvm_BIOS_15_LISTST
+	!word zvm_BIOS_16_SECTRN
+	!word zvm_BIOS_17_CONOST
+	!word zvm_BIOS_18_AUXIST
+	!word zvm_BIOS_19_AUXOST
+	!word zvm_BIOS_20_DEVTBL
+	!word zvm_BIOS_21_DEVINI
+	!word zvm_BIOS_22_DRVTBL
+	!word zvm_BIOS_23_MULTIO
+	!word zvm_BIOS_24_FLUSH
+	!word zvm_BIOS_25_MOVE
+	!word zvm_BIOS_26_TIME
+	!word zvm_BIOS_27_SELMEM
+	!word zvm_BIOS_28_SETBNK
+	!word zvm_BIOS_29_XMOVE
+	!word zvm_BIOS_30_USERF
+	!word zvm_BIOS_31_RESERV1
+	!word zvm_BIOS_32_RESERV2
+
+zvm_BIOS_00_BOOT:            ; Cold start
+
+	; XXX !!!
+
+	; FALLTROUGH
+
+zvm_BIOS_01_WBOOT:           ; Warm start
+zvm_BIOS_31_RESERV1:         ; Reserved   
+zvm_BIOS_32_RESERV2:         ; Reserved
+
+	; XXX !!!
+
+zvm_BIOS_02_CONST:           ; Check if input character available
+
+	; XXX !!!
+
+zvm_BIOS_03_CONIN:           ; Console input
+
+	; XXX !!!
+
+zvm_BIOS_04_CONOUT:          ; Console output
+
+	; XXX
+
+zvm_BIOS_05_LIST:            ; Provide list of character output devices
+
+	; XXX
+
+zvm_BIOS_06_AUXOUT:          ; AUX output
+
+	; XXX
+
+zvm_BIOS_07_AUXIN:           ; AUX input
+
+	; XXX
+
+zvm_BIOS_08_HOME:            ; Go to track 0
+
+	; XXX !!!
+
+zvm_BIOS_09_SELDSK:          ; Select drive
+
+	; XXX !!!
+
+zvm_BIOS_10_SETTRK:          ; Set track number
+
+	; XXX !!!
+
+zvm_BIOS_11_SETSEC:          ; Set sector number
+
+	; XXX !!!
+
+zvm_BIOS_12_SETDMA:          ; Set DMA address
+
+	; XXX !!!
+
+zvm_BIOS_13_READ:            ; Read sector
+
+	; XXX !!!
+
+zvm_BIOS_14_WRITE:           ; Write sector
+
+	; XXX !!!
+
+zvm_BIOS_15_LISTST:          ; List status
+
+	; XXX
+
+zvm_BIOS_16_SECTRN:          ; Convert logical to physical sector
+
+	; XXX !!!
+
+zvm_BIOS_17_CONOST:          ; Console output status
+
+	; XXX
+
+zvm_BIOS_18_AUXIST:          ; AUX input status
+
+	; XXX
+
+zvm_BIOS_19_AUXOST:          ; AUX output status
+
+	; XXX
+
+zvm_BIOS_20_DEVTBL:          ; Character device table address
+
+	; XXX
+
+zvm_BIOS_21_DEVINI:          ; Initialize character device
+
+	; XXX
+
+zvm_BIOS_22_DRVTBL:          ; Disk drive table address
+
+	; XXX
+
+zvm_BIOS_23_MULTIO:          ; Set number of logically consecutive sectors
+
+	; XXX !!!
+
+zvm_BIOS_24_FLUSH:           ; Force buffer flushing for user deblocking
+
+	; XXX !!!
+
+zvm_BIOS_25_MOVE:            ; Memory move
+
+	; XXX
+
+zvm_BIOS_26_TIME:            ; Get or set time
+
+	; XXX !!!
+
+zvm_BIOS_27_SELMEM:          ; Select memory bank
+
+	; XXX
+
+zvm_BIOS_28_SETBNK:          ; Set bank for DMA operation
+
+	; XXX
+
+zvm_BIOS_29_XMOVE:           ; Set bank if buffer is in bank other than 1 or 2
+
+	; XXX
+
+zvm_BIOS_30_USERF:           ; Implementation-specific functionality
+
+	; XXX implement function to save RAM DISK back to SD CARD