Add upload tooling for BASIC shell

This shaves off quite a few bytes from the binary.

apps/basic/README.md

@@ -149,6 +149,11 @@ input I/O on port 42 and stores the byte result in `A`.
 **out <port> <val>**: Same thing as `poke`, but for a I/O port. `out 42 1+2`
 generates an output I/O on port 42 with value 3.
 
+**getc**: Waits for a single character to be typed in the console and then puts
+that value in `A`.
+
+**putc <char>**: Puts the specified character to the console.
+
 **sleep <units>**: Sleep a number of "units" specified by the supplied
 expression. A "unit" depends on the CPU clock speed. At 4MHz, it is roughly 8
 microseconds.

apps/basic/blk.asm

@@ -26,6 +26,8 @@ basGETB:
 	call	blkGetB
 	ret	nz
 	ld	(VAR_TBL), a
+	xor	a
+	ld	(VAR_TBL+1), a
 	ret
 
 basPUTB:
@@ -36,12 +38,12 @@ basPUTB:
 	jp	blkPutB
 
 basBLKCmds:
+	.db	"bsel", 0
 	.dw	basBSEL
-	.db	"bsel", 0, 0
-	.dw	basBSEEK
 	.db	"bseek", 0
+	.dw	basBSEEK
+	.db	"getb", 0
 	.dw	basGETB
-	.db	"getb", 0, 0
+	.db	"putb", 0
 	.dw	basPUTB
-	.db	"putb", 0, 0
-	.db	0xff, 0xff, 0xff	; end of table
+	.db	0xff		; end of table

apps/basic/fs.asm

@@ -127,14 +127,14 @@ basPgmHook:
 	ret
 
 basFSCmds:
+	.db	"fls", 0
 	.dw	basFLS
-	.db	"fls", 0, 0, 0
-	.dw	basLDBAS
 	.db	"ldbas", 0
-	.dw	basFOPEN
+	.dw	basLDBAS
 	.db	"fopen", 0
+	.dw	basFOPEN
+	.db	"fnew", 0
 	.dw	basFNEW
-	.db	"fnew", 0, 0
+	.db	"fdel", 0
 	.dw	basFDEL
-	.db	"fdel", 0, 0
-	.db	0xff, 0xff, 0xff	; end of table
+	.db	0xff		; end of table

apps/basic/main.asm

@@ -31,7 +31,7 @@ basStart:
 	jr	basLoop
 
 .welcome:
-	.db "OK", 0
+	.db "Collapse OS", 0
 
 basLoop:
 	ld	hl, .sPrompt
@@ -63,19 +63,18 @@ basLoop:
 ; Destroys HL.
 ; Z is set if found, unset otherwise.
 basFindCmd:
-	; cmd table starts with routine pointer, skip
-	inc	hl \ inc hl
 .loop:
 	call	strcmp
-	jr	z, .found
-	ld	a, 8
-	call	addHL
+	call	strskip
+	inc	hl		; point to routine
+	jr	z, .found	; Z from strcmp
+	inc	hl \ inc hl	; skip routine
 	ld	a, (hl)
-	cp	0xff
-	jr	nz, .loop
-	jp	unsetZ
+	inc	a		; was it 0xff?
+	jr	nz, .loop	; no
+	dec	a		; unset Z
+	ret
 .found:
-	dec	hl \ dec hl
 	call	intoHL
 	push	hl \ pop ix
 	ret
@@ -126,16 +125,11 @@ basERR:
 ;
 ; Commands are expected to set Z on success.
 basBYE:
-	ld	hl, .sBye
-	call	printstr
-	call	printcrlf
 	; To quit the loop, let's return the stack to its initial value and
 	; then return.
 	xor	a
 	ld	sp, (BAS_INITSP)
 	ret
-.sBye:
-	.db	"Goodbye!", 0
 
 basLIST:
 	call	bufFirst
@@ -349,6 +343,22 @@ basIN:
 	; Z set from rdExpr
 	ret
 
+basGETC:
+	call	stdioGetC
+	ld	(VAR_TBL), a
+	xor	a
+	ld	(VAR_TBL+1), a
+	ret
+
+basPUTC:
+	call	rdExpr
+	ret	nz
+	push	ix \ pop hl
+	ld	a, l
+	call	stdioPutC
+	xor	a	; set Z
+	ret
+
 basSLEEP:
 	call	rdExpr
 	ret	nz
@@ -425,42 +435,49 @@ basR2Var:	; Just send reg to vars. Used in basPgmHook
 	cp	a		; USR never errors out
 	ret
 
+; Command table format: Null-terminated string followed by a 2-byte routine
+; pointer.
+
 ; direct only
 basCmds1:
+	.db	"bye", 0
 	.dw	basBYE
-	.db	"bye", 0, 0, 0
+	.db	"list", 0
 	.dw	basLIST
-	.db	"list", 0, 0
+	.db	"run", 0
 	.dw	basRUN
-	.db	"run", 0, 0, 0
-	.dw	bufInit
 	.db	"clear", 0
+	.dw	bufInit
 ; statements
 basCmds2:
-	.dw	basPRINT
 	.db	"print", 0
+	.dw	basPRINT
+	.db	"goto", 0
 	.dw	basGOTO
-	.db	"goto", 0, 0
+	.db	"if", 0
 	.dw	basIF
-	.db	"if", 0, 0, 0, 0
-	.dw	basINPUT
 	.db	"input", 0
+	.dw	basINPUT
+	.db	"peek", 0
 	.dw	basPEEK
-	.db	"peek", 0, 0
+	.db	"poke", 0
 	.dw	basPOKE
-	.db	"poke", 0, 0
+	.db	"deek", 0
 	.dw	basDEEK
-	.db	"deek", 0, 0
+	.db	"doke", 0
 	.dw	basDOKE
-	.db	"doke", 0, 0
+	.db	"out", 0
 	.dw	basOUT
-	.db	"out", 0, 0, 0
+	.db	"in", 0
 	.dw	basIN
-	.db	"in", 0, 0, 0, 0
-	.dw	basSLEEP
+	.db	"getc", 0
+	.dw	basGETC
+	.db	"putc", 0
+	.dw	basPUTC
 	.db	"sleep", 0
+	.dw	basSLEEP
+	.db	"addr", 0
 	.dw	basADDR
-	.db	"addr", 0, 0
+	.db	"usr", 0
 	.dw	basUSR
-	.db	"usr", 0, 0, 0
-	.db	0xff, 0xff, 0xff	; end of table
+	.db	0xff	; end of table

apps/lib/util.asm

@@ -52,6 +52,19 @@ strcmp:
 	; early, set otherwise)
 	ret
 
+; Given a string at (HL), move HL until it points to the end of that string.
+strskip:
+	push	af
+	xor	a	; look for null char
+.loop:
+	cp	(hl)
+	jp	z, .found
+	inc	hl
+	jr	.loop
+.found:
+	pop	af
+	ret
+
 ; Returns length of string at (HL) in A.
 ; Doesn't include null termination.
 strlen:

doc/load-run-code.md

@@ -126,3 +126,16 @@ You can then include that file in your "user" code, like this:
 
 If you load that code at `0xa000` and call it, it will print "Hello World!" by
 using the `printstr` routine from `core.asm`.
+
+## Doing the same with the BASIC shell
+
+The BASIC shell also has the capacity to load code from serial console but its
+semantic is a bit different from the regular shell. Instead of peeking and
+poking, you use `getc` to send data and then `putc` to send the same data back
+for verification. Then, you can use `poke` to commit it to memory.
+
+There's an upload tool that use these commands and it's `uploadb.py`. It is
+invoked with the same arguments as `upload.py`.
+
+Once your code is uploaded, you will call it with BASIC's `usr` command. See
+BASIC's README for more details.

tools/uploadb.py

@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+
+# Push specified file to specified device **running the BASIC shell** and verify
+# that the sent contents is correct.
+
+import argparse
+import os
+import sys
+
+def sendcmd(fd, cmd):
+    # The serial link echoes back all typed characters and expects us to read
+    # them. We have to send each char one at a time.
+    if isinstance(cmd, str):
+        cmd = cmd.encode()
+    for c in cmd:
+        os.write(fd, bytes([c]))
+        os.read(fd, 1)
+    os.write(fd, b'\n')
+    os.read(fd, 2)  # sends back \r\n
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('device')
+    parser.add_argument('memptr')
+    parser.add_argument('filename')
+    args = parser.parse_args()
+
+    try:
+        memptr = int('0x' + args.memptr, 0)
+    except ValueError:
+        print("memptr are has to be hexadecimal without prefix.")
+        return 1
+    if memptr >= 0x10000:
+        print("memptr out of range.")
+        return 1
+    maxsize = 0x10000 - memptr
+    st = os.stat(args.filename)
+    if st.st_size > maxsize:
+        print("File too big. 0x{:04x} bytes max".format(maxsize))
+        return 1
+    fd = os.open(args.device, os.O_RDWR)
+    with open(args.filename, 'rb') as fp:
+        fcontents = fp.read()
+    sendcmd(fd, f'm=0x{memptr:04x}')
+    os.read(fd, 2) # read prompt
+
+    for i, c in enumerate(fcontents):
+        c = bytes([c])
+        sendcmd(fd, 'getc')
+        os.write(fd, c)
+        os.read(fd, 2) # read prompt
+        sendcmd(fd, 'putc a')
+        r = os.read(fd, 1) # putc result
+        os.read(fd, 2) # read prompt
+        if r != c:
+            print(f"Mismatch at byte {i}! {c} != {r}")
+        sendcmd(fd, 'poke m a')
+        os.read(fd, 2) # read prompt
+        sendcmd(fd, 'm=m+1')
+        os.read(fd, 2) # read prompt
+    print("Done!")
+    os.close(fd)
+    return 0
+
+if __name__ == '__main__':
+    sys.exit(main())