CH Driver Tweaks

zxcc: Fix for load bios.bin failure on a RPi4

Source/HBIOS/ch.asm

@@ -9,7 +9,7 @@
 ; his code in FUZIX (https://github.com/EtchedPixels/FUZIX).
 ;
 ; NOTES:
-;  - There seem to compatibility issues with older USB thumb drives.
+;  - There seem to be compatibility issues with older USB thumb drives.
 ;    Such drives will complete DISK_INIT successfully, but then return
 ;    an error attempting to do any I/O.  The error is $17 indicating
 ;    the CH37x encountered an overflow during communication with the
@@ -21,13 +21,13 @@
 ;    will clear this, but the RESET_ALL command is very problematic on
 ;    the CH376.  On the CH376, the hardware reset takes a very long
 ;    time (much longer than the documentation suggests).  It seems to
-;    work find on the CH375, but since you don't know what chip you
+;    work fine on the CH375, but since you don't know what chip you
 ;    are dealing with at that point, I have given up on using it.
 ;
 ; TODO:
 ;  - Implement auto-recovery on error status.
 ;
-CHUSB_FASTIO	.EQU	FALSE		; USE INIR/OTIR?
+CHUSB_FASTIO	.EQU	TRUE		; USE INIR/OTIR?
 ;
 ; PORT OFFSETS FROM BASE PORT
 ;
@@ -324,7 +324,7 @@ CH_FLUSH1:
 ;
 ;
 CH_DETECT:
-	PRTS("\r\nDETECT:$")		; *DEBUG*
+	;PRTS("\r\nDETECT:$")		; *DEBUG*
 CH_DETECT1:
 	LD	A,CH_CMD_EXIST		; LOAD COMMAND
 	CALL	CH_CMD			; SEND COMMAND

Source/ver.inc

@@ -2,7 +2,7 @@
 #DEFINE	RMN	3
 #DEFINE	RUP	0
 #DEFINE	RTP	0
-#DEFINE BIOSVER	"3.3.0-dev.56"
+#DEFINE BIOSVER	"3.3.0-dev.57"
 #define rmj	RMJ
 #define rmn	RMN
 #define rup	RUP

Source/ver.lib

@@ -3,5 +3,5 @@ rmn	equ	3
 rup	equ	0
 rtp	equ	0
 biosver	macro
-	db	"3.3.0-dev.56"
+	db	"3.3.0-dev.57"
 	endm

Tools/unix/zxcc/zxcc.c

@@ -127,7 +127,15 @@ void load_bios(void)
 		uint32_t size = CPM_MAXPATH - 8;
 		_NSGetExecutablePath(dir, &size);
 #else
-		readlink("/proc/self/exe", dir, CPM_MAXPATH - 8);   /* allow room for bios.bin */
+		ssize_t len;
+		len = readlink("/proc/self/exe", dir, CPM_MAXPATH - 8);   /* allow room for bios.bin */
+		if (len < 0)
+		{
+			/* len of -1 indicates an error occurred */
+			len = 0;
+		}
+		/* Terminate the dir string with a NUL character */
+		dir[len] = 0;
 #endif
 		q = strrchr(dir, DIRSEPCH);
 		*++q = 0;