static int lpc2900_handle_signature_command( struct command_context_s *cmd_ctx,
                                              char *cmd, char **args, int argc )
 {
-       flash_bank_t *bank;
        uint32_t status;
        uint32_t signature[4];
 
                return ERROR_FLASH_BANK_INVALID;
        }
 
-       /* Get the bank descriptor */
-       bank = get_flash_bank_by_num( strtoul(args[0], NULL, 0) );
-       if( !bank )
-       {
-               command_print( cmd_ctx, "flash bank '#%s' is out of bounds", args[0] );
-               return ERROR_OK;
-       }
+       flash_bank_t *bank;
+       int retval = flash_command_get_bank_by_num(cmd_ctx, args[0], &bank);
+       if (ERROR_OK != retval)
+               return retval;
 
        if( bank->target->state != TARGET_HALTED )
        {
 static int lpc2900_handle_read_custom_command( struct command_context_s *cmd_ctx,
                                                char *cmd, char **args, int argc )
 {
-       flash_bank_t *bank;
-
-
        if( argc < 2 )
        {
                return ERROR_COMMAND_SYNTAX_ERROR;
        }
 
-       /* Get the bank descriptor */
-       bank = get_flash_bank_by_num( strtoul(args[0], NULL, 0) );
-       if( !bank )
-       {
-               command_print( cmd_ctx, "flash bank '#%s' is out of bounds", args[0] );
-               return ERROR_OK;
-       }
+       flash_bank_t *bank;
+       int retval = flash_command_get_bank_by_num(cmd_ctx, args[0], &bank);
+       if (ERROR_OK != retval)
+               return retval;
+
        lpc2900_flash_bank_t *lpc2900_info = bank->driver_priv;
        lpc2900_info->risky = 0;
 
 static int lpc2900_handle_password_command(struct command_context_s *cmd_ctx,
                                            char *cmd, char **args, int argc)
 {
-       flash_bank_t *bank;
-
-
        if (argc < 2)
        {
                return ERROR_COMMAND_SYNTAX_ERROR;
        }
 
-       /* Get the bank descriptor */
-       bank = get_flash_bank_by_num(strtoul(args[0], NULL, 0));
-       if (!bank)
-       {
-               command_print(cmd_ctx, "flash bank '#%s' is out of bounds", args[0]);
-               return ERROR_OK;
-       }
+       flash_bank_t *bank;
+       int retval = flash_command_get_bank_by_num(cmd_ctx, args[0], &bank);
+       if (ERROR_OK != retval)
+               return retval;
+
        lpc2900_flash_bank_t *lpc2900_info = bank->driver_priv;
 
 #define ISS_PASSWORD "I_know_what_I_am_doing"
                return ERROR_COMMAND_SYNTAX_ERROR;
        }
 
-       /* Get the bank descriptor */
-       flash_bank_t *bank = get_flash_bank_by_num(strtoul(args[0], NULL, 0));
-       if (!bank)
-       {
-               command_print(cmd_ctx, "flash bank '#%s' is out of bounds", args[0]);
-               return ERROR_OK;
-       }
+       flash_bank_t *bank;
+       int retval = flash_command_get_bank_by_num(cmd_ctx, args[0], &bank);
+       if (ERROR_OK != retval)
+               return retval;
+
        lpc2900_flash_bank_t *lpc2900_info = bank->driver_priv;
 
        /* Check if command execution is allowed. */
 
        char *filename = args[1];
        char *type = (argc >= 3) ? args[2] : NULL;
-       int retval = image_open(&image, filename, type);
+       retval = image_open(&image, filename, type);
        if (retval != ERROR_OK)
        {
                return retval;
        }
 
        /* Get the bank descriptor */
-       flash_bank_t *bank = get_flash_bank_by_num(strtoul(args[0], NULL, 0));
-       if (!bank)
-       {
-               command_print(cmd_ctx, "flash bank '#%s' is out of bounds", args[0]);
-               return ERROR_OK;
-       }
+       flash_bank_t *bank;
+       int retval = flash_command_get_bank_by_num(cmd_ctx, args[0], &bank);
+       if (ERROR_OK != retval)
+               return retval;
+
        lpc2900_flash_bank_t *lpc2900_info = bank->driver_priv;
 
        /* Check if command execution is allowed. */
        lpc2900_info->risky = 0;
 
        /* Read sector range, and do a sanity check. */
-       int first = strtoul(args[1], NULL, 0);
-       int last = strtoul(args[2], NULL, 0);
+       int first, last;
+       COMMAND_PARSE_NUMBER(int, args[1], first);
+       COMMAND_PARSE_NUMBER(int, args[2], last);
        if( (first >= bank->num_sectors) ||
            (last >= bank->num_sectors) ||
            (first > last) )
 
        uint8_t page[FLASH_PAGE_SIZE];
        int sector;
-       int retval;
 
        /* Sectors in page 6 */
        if( (first <= 4) || (last >= 8) )
        }
 
        /* Get the bank descriptor */
-       flash_bank_t *bank = get_flash_bank_by_num(strtoul(args[0], NULL, 0));
-       if (!bank)
-       {
-               command_print(cmd_ctx, "flash bank '#%s' is out of bounds", args[0]);
-               return ERROR_OK;
-       }
+       flash_bank_t *bank;
+       int retval = flash_command_get_bank_by_num(cmd_ctx, args[0], &bank);
+       if (ERROR_OK != retval)
+               return retval;
+
        lpc2900_flash_bank_t *lpc2900_info = bank->driver_priv;
 
        /* Check if command execution is allowed. */
        page[0x30 +  3] = 0x7F;
 
        /* Write to page 5 */
-       int retval;
        if( (retval = lpc2900_write_index_page( bank, 5, &page ))
                        != ERROR_OK )
        {
         * Reject it if we can't meet the requirements for program time
         * (if clock too slow), or for erase time (clock too fast).
         */
-       lpc2900_info->clk_sys_fmc = strtoul(args[6], NULL, 0) * 1000;
+       uint32_t clk_sys_fmc;
+       COMMAND_PARSE_NUMBER(u32, args[6], clk_sys_fmc);
+       lpc2900_info->clk_sys_fmc = clk_sys_fmc * 1000;
 
        uint32_t clock_limit;
        /* Check program time limit */