Allow getting the CCP/CONSOLE driver names, not just setting

This improves the value of our utilities.

Author: skx

EXTENSIONS.md

@@ -51,25 +51,29 @@ Demonstrated in [samples/ctrlc.z80](samples/ctrlc.z80).
 
 
 
-## Function 0x02: Change Console Driver
+## Function 0x02: Get/Set Console Driver
 
 On entry DE points to a text-string, terminated by NULL, which represents the name of the
 console output driver to use.
 
+If DE is 0x0000 then the DMA area is filled with the name of the current driver, NULL-terminated.
+
 Demonstrated in [samples/console.z80](samples/console.z80)
 
 
 
-## Function 0x03: Change CCP Driver
+## Function 0x03: Get/Set CCP
 
 On entry DE points to a text-string, terminated by NULL, which represents the name of the
 CCP to use.
 
+If DE is 0x0000 then the DMA area is filled with the name of the currently active CCP, NULL-terminated.
+
 Demonstrated in [samples/ccp.z80](samples/ccp.z80)
 
 
 
-## Function 0x04: Set Quiet
+## Function 0x04: Get/Set Quiet
 
 * If C is 0x00 quiet-mode is enabled.
 * If C is 0x01 quiet-mode is disabled.

cpm/cpm_bios.go

@@ -245,6 +245,25 @@ func BiosSysCallReserved1(cpm *CPM) error {
 		}
 
 	case 0x0002:
+
+		if de == 0x0000 {
+			// Fill the DMA area with NULL bytes
+			addr := cpm.dma
+
+			end := addr + uint16(127)
+			for end > addr {
+				cpm.Memory.Set(end, 0x00)
+				end--
+			}
+
+			// now populate with our console driver
+			str := cpm.output.GetName()
+			for i, c := range str {
+				cpm.Memory.Set(addr+uint16(i), uint8(c))
+			}
+			return nil
+		}
+
 		// Get the string pointed to by DE
 		str := getStringFromMemory(de)
 
@@ -274,6 +293,24 @@ func BiosSysCallReserved1(cpm *CPM) error {
 
 	case 0x0003:
 
+		if de == 0x0000 {
+			// Fill the DMA area with NULL bytes
+			addr := cpm.dma
+
+			end := addr + uint16(127)
+			for end > addr {
+				cpm.Memory.Set(end, 0x00)
+				end--
+			}
+
+			// now populate with our CCP
+			str := cpm.ccp
+			for i, c := range str {
+				cpm.Memory.Set(addr+uint16(i), uint8(c))
+			}
+			return nil
+		}
+
 		// Get the string pointed to by DE
 		str := getStringFromMemory(de)
 

samples/ccp.com

@@ -38,7 +38,7 @@ BDOS_ENTRY_POINT:     EQU 5
         ;; then we've got nothing specified
         ld a, (FCB1 + 1)
         cp 0x20                  ; 0x20 = 32 == SPACE
-        jp z, missing_argument   ; Got a space, report the error
+        jp z, show_ccp          ; Got a space, show the CCP
 
         ld HL, 03
         ld de, FCB1 + 1
@@ -49,15 +49,39 @@ exit:
         LD      C,0x00
         CALL    BDOS_ENTRY_POINT
 
-;;
-;; Error Routines
-;;
-missing_argument:
-        LD DE, MISSING_ARGUMENT_STR
+
+;; Show the current CCP
+show_ccp:
+        LD DE, CCP_PREFIX
         LD C, BDOS_OUTPUT_STRING
-        call BDOS_ENTRY_POINT
+        CALL BDOS_ENTRY_POINT
+
+        ld HL, 03
+        ld de, 0x0000
+        ld a, 31
+        out (0xff), a
+
+        LD HL, 0x0080
+loopy:
+        LD A, (HL)
+        cp 0
+        JR Z, finished_loop
+        push HL
+             ld e,a
+             ld c, 0x02
+             call 0x0005
+        pop HL
+        inc hl
+        jr loopy
+finished_loop:
+        LD DE, CCP_SUFFIX
+        LD C, BDOS_OUTPUT_STRING
+        CALL BDOS_ENTRY_POINT
         jr exit
 
+;;
+;; Error Routines
+;;
 not_cpmulator:
         LD DE, WRONG_EMULATOR
         LD C, BDOS_OUTPUT_STRING
@@ -68,8 +92,11 @@ not_cpmulator:
 ;;
 ;; Text output strings.
 ;;
-MISSING_ARGUMENT_STR:
-        db "Usage: CCP [CCP|CCPZ]", 0x0a, 0x0d, "$"
+CCP_PREFIX:
+        db "CCP is set to '$"
+CCP_SUFFIX:
+        db "'", 0x0a, 0x0d, "$"
+
 WRONG_EMULATOR:
         db "This binary is not running under cpmulator, aborting.", 0x0a, 0x0d, "$"
 

samples/ccp.z80

@@ -36,7 +36,7 @@ BDOS_OUTPUT_STRING:   EQU 9
         ;; then we've got nothing specified
         ld a, (FCB1 + 1)
         cp 0x20                  ; 0x20 = 32 == SPACE
-        jp z, missing_argument   ; Got a space, report the error
+        jp z, show_driver        ; Got a space, show the console driver name
 
 
         ;; OK we're running under cpmulator
@@ -50,14 +50,38 @@ exit:
         LD      C,0x00
         CALL    BDOS_ENTRY_POINT
 
+;; Show the current console driver
+show_driver:
+        LD DE, CONSOLE_PREFIX
+        LD C, BDOS_OUTPUT_STRING
+        CALL BDOS_ENTRY_POINT
+
+        ld HL, 02
+        ld de, 0x0000
+        ld a, 31
+        out (0xff), a
+
+        LD HL, 0x0080
+loopy:
+        LD A, (HL)
+        cp 0
+        JR Z, finished_loop
+        push HL
+             ld e,a
+             ld c, 0x02
+             call 0x0005
+        pop HL
+        inc hl
+        jr loopy
+finished_loop:
+        LD DE, CONSOLE_SUFFIX
+        LD C, BDOS_OUTPUT_STRING
+        CALL BDOS_ENTRY_POINT
+        jr exit
+
 ;;
 ;; Error Routines
 ;;
-missing_argument:
-        LD DE, MISSING_ARGUMENT_STR
-        LD C, BDOS_OUTPUT_STRING
-        call BDOS_ENTRY_POINT
-        jr exit
 
 not_cpmulator:
         LD DE, WRONG_EMULATOR
@@ -69,8 +93,10 @@ not_cpmulator:
 ;;
 ;; Text output strings.
 ;;
-MISSING_ARGUMENT_STR:
-        db "Usage: console [adm-3a|ansi]", 0x0a, 0x0d, "$"
+CONSOLE_PREFIX:
+        db "Console driver is set to '$"
+CONSOLE_SUFFIX:
+        db "'", 0x0a, 0x0d, "$"
 WRONG_EMULATOR:
         db "This binary is not running under cpmulator, aborting.", 0x0a, 0x0d, "$"
 END