diff --git a/testcode/lib/tinyshell.c b/testcode/lib/tinyshell.c
index f4a18126b..141065257 100644
--- a/testcode/lib/tinyshell.c
+++ b/testcode/lib/tinyshell.c
@@ -5,12 +5,22 @@
 
 #define VERSION_ASC "0.90"
 
-#define KEYB_BUFSZ 80
-#define PROMPT ">>> "
 #ifdef __ATARI__
 #define UPPERCASE      /* define (e.g. for Atari) to convert filenames etc. to upper case */
+#define HAVE_SUBDIRS
 #endif
 
+#ifdef __APPLE2__
+#define HAVE_SUBDIRS
+#endif
+
+#ifdef __CC65__
+#define CHECK_SP
+#endif
+
+#define KEYB_BUFSZ 80
+#define PROMPT ">>> "
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -19,6 +29,7 @@
 #ifndef __CC65__
 #include <sys/stat.h>
 #include <sys/param.h>
+#define HAVE_SUBDIRS
 #else
 #define MAXPATHLEN 64
 #endif
@@ -26,6 +37,10 @@
 #include <fcntl.h>
 #include <dirent.h>
 
+#ifdef CHECK_SP
+extern unsigned int getsp(void);  /* comes from getsp.s */
+#endif
+
 #define CMD_NOTHING 0
 #define CMD_INVALID 1
 #define CMD_HELP    2
@@ -38,7 +53,10 @@
 #define CMD_RENAME  9
 #define CMD_COPY    10
 #define CMD_PWD     11
+#define CMD_CLS     12
+#define CMD_VERBOSE 13
 
+static unsigned char verbose;
 static unsigned char terminate;
 static unsigned char cmd;
 static unsigned char *cmd_asc, *arg1, *arg2, *arg3;
@@ -56,11 +74,13 @@ struct cmd_table {
     { "ls",    CMD_LS },
     { "dir",   CMD_LS },
     { "md",    CMD_MKDIR },
+#ifdef HAVE_SUBDIRS
     { "mkdir", CMD_MKDIR },
     { "rd",    CMD_RMDIR },
     { "rmdir", CMD_RMDIR },
     { "cd",    CMD_CHDIR },
     { "chdir", CMD_CHDIR },
+#endif
     { "rm",    CMD_RM },
     { "del",   CMD_RM },
     { "cp",    CMD_COPY },
@@ -68,6 +88,10 @@ struct cmd_table {
     { "mv",    CMD_RENAME },
     { "ren",   CMD_RENAME },
     { "pwd",   CMD_PWD },
+#ifdef __ATARI__
+    { "cls",   CMD_CLS },
+#endif
+    { "verbose", CMD_VERBOSE },
     { NULL, 0 }
 };
 
@@ -82,6 +106,22 @@ static void get_command(void)
 {
     unsigned char i = 0;
 
+#ifdef CHECK_SP
+    static char firstcall = 1;
+    static unsigned int good_sp;
+    unsigned int sp;
+    if (firstcall)
+        sp = good_sp = getsp();
+    else
+        sp = getsp();
+
+    if (sp != good_sp) {
+        printf("SP: 0x%04X  ***MISMATCH*** 0x%04X\n", sp, good_sp);
+    }
+    else if (verbose)
+        printf("SP: 0x%04X\n", sp);
+#endif
+
     arg1 = arg2 = arg3 = NULL;
 
     /* issue prompt */
@@ -132,6 +172,10 @@ static void cmd_help(void)
     puts("cd, chdir  -  change directory or drive");
     puts("md, mkdir  -  make directory or drive");
     puts("rd, rmdir  -  remove directory or drive");
+#ifdef __ATARI__
+    puts("cls        -  clear screen");
+#endif
+    puts("verbose    -  set verbosity level");
     puts("sorry, you cannot start programs here");
 }
 
@@ -173,6 +217,8 @@ static void cmd_ls(void)
     else
         arg = ".";
 
+    if (verbose)
+        printf("Buffer addr: %p\n", arg);
     dir = opendir(arg);
 #ifdef __ATARI__
     if (need_free) free(arg);
@@ -203,6 +249,8 @@ static void cmd_rm(void)
         printf("remove failed: %s\n", strerror(errno));
 }
 
+#ifdef HAVE_SUBDIRS
+
 static void cmd_mkdir(void)
 {
     if (!arg1 || arg2) {
@@ -262,6 +310,8 @@ static void cmd_pwd(void)
         printf("malloc %u bytes failed: %s\n", MAXPATHLEN, strerror(errno));
         return;
     }
+    if (verbose)
+        printf("Buffer addr: %p\n", buf);
     if (!getcwd(buf, MAXPATHLEN)) {
         printf("getcwd failed: %s\n", strerror(errno));
         free(buf);
@@ -272,6 +322,8 @@ static void cmd_pwd(void)
     free(buf);
 }
 
+#endif /* #ifdef HAVE_SUBDIRS */
+
 static void cmd_rename(void)
 {
     if (!arg2 || arg3) {
@@ -309,6 +361,8 @@ static void cmd_copy(void)
         printf("malloc %u bytes failed: %s\n", cpbuf_sz, strerror(errno));
         return;
     }
+    if (verbose)
+        printf("Buffer addr: %p\n", buf);
 
     while (1) {
         if (srcfd == -1) {
@@ -349,6 +403,33 @@ static void cmd_copy(void)
     if (dstfd >= 0) close(dstfd);
 }
 
+#ifdef __ATARI__
+static void cmd_cls(void)
+{
+    printf("\f");
+}
+#endif
+
+static void cmd_verbose(void)
+{
+    unsigned long verb;
+    char *endptr;
+
+    if (!arg1 || arg2) {
+        puts("usage: verbose <level>");
+        return;
+    }
+
+    verb = strtoul(arg1, &endptr, 10);
+    if (verb > 255 || *endptr) {
+        puts("invalid verbosity level");
+        return;
+    }
+
+    verbose = verb;
+    printf("verbosity level set to %d\n", verbose);
+}
+
 static void run_command(void)
 {
     switch (cmd) {
@@ -359,12 +440,18 @@ static void run_command(void)
         case CMD_QUIT: terminate = 1; return;
         case CMD_LS: cmd_ls(); return;
         case CMD_RM: cmd_rm(); return;
+#ifdef HAVE_SUBDIRS
         case CMD_CHDIR: cmd_chdir(); return;
         case CMD_MKDIR: cmd_mkdir(); return;
         case CMD_RMDIR: cmd_rmdir(); return;
         case CMD_PWD: cmd_pwd(); return;
+#endif
         case CMD_RENAME: cmd_rename(); return;
         case CMD_COPY: cmd_copy(); return;
+#ifdef __ATARI__
+        case CMD_CLS: cmd_cls(); return;
+#endif
+        case CMD_VERBOSE: cmd_verbose(); return;
     }
 }