NavCom LAND-PAK Rev.N User Manual

Page 99

Technical Reference Manual Rev. N

Blk = All;

Blu = IOP w/Internal Radio

;

Red = IOP & LBM

;

Grn = Engine only

0x03 – Delete Files (specified by name)

In order to delete files, the user should send a request message with the “special” bits of W3
specified as above. (This is a safety feature to guard against inadvertent erasure.) The
user should also specify a file name mask. Any files matching this mask will be irretrievably
deleted from the file system.

The response from the IOP includes a result bit (bit 1 of W6) which will be set to 1 if the
“special” bits in the request were set incorrectly. Otherwise, bit 1 of W6 will be zero, and the
response will indicate the number of files successfully deleted. In W8, the response will
contain a copy of the file name mask from the request message.

In order to preserve word alignment, the length of each file name, including null terminators,
should be even. If necessary, an extra null terminator (‘\0’ character) should be appended
to support this requirement. For example, a file name TEST.TXT consists of eight
characters plus a null terminator, for a total of nine. An extra null terminator should be
added in this case to bring the total number of bytes to ten. The same convention will be
used for the file names in the response message.

Request

Record
Usage

Command - Yes
Response - No

Input: Delete selected file(s) request;
Output: see table below

Ref

Message Field Description

Data Type Units

Range

Scale

Byte

Count

STX

(hex)

U08

PRA1 99 (hex)

U08

PRA2 66 (hex)

U08

7e(hex)

U08

Length 0xXXXX

U16

Sub ID 0x03

U08

0x00 (request)

U08

Special

B7 = 1
B6 = 1
B5 = 0
B4 = 1
B3-B0: Spare (don’t care)

U08

Filename String (Null Terminated

String)
Supports DOS 8.3 filenames.
Supports wild card characters
‘*’ and ‘?’
‘?’ – Single character wild card
‘*’ – String wild card

U08[]

1[]

CKSM Checksum

U08

ETX

(hex)

U08