Loading Files & Data
There have been some minor changes to this page since the introduction of version 2.xx, the old page has been archived here.
This section deals with the various methods of getting programs and data into the BV513, this is complicated by the fact that there is more than one method of transferring data and there are three places that it could be transferred to. In addition to this some translation can take place depending on which command is used.
NOTE: Xmodem transfer is no longer available in Verison 2.xx. This section explains the various options that are available for transferring data into the BV513
Text Transfer (tload)
The 'tload' command will take a text file using the ACK protocol (see box) and either load to RAM or to the SD Card depending on the syntax used.
This is a very simple text transfer protocol that does not rely on any hardware communications hand shake and works in the following way. The BV513 requests a line of text from BV-Comm by sending an ACK (ASCII 6). BV-Comm will send just one line of text and then wait for another ACK request. This gives time for the BV513 to process the line at its own pace. In addition there is a time out on the BV-Comm side that will only wait, approximately 1 second for the ACK request. If it is not received, BV-Comm assumes that no more data is required and terminates the process.
Setting BV-Comm
To use the text transfer with 'tload' BV-Comm must be
correctly set up. Use this
icon to get the text settings dialog box.
Set the dialog box as shown above. This will send the 'tload' command automatically just saving a few keystrokes. The most important part is that the end of line character is set to 6 and checked. The transfer path can be ignored.
The tload command, unlike reload and xload does not clear the program space beforehand so you must remember to use 'new' before loading a file. You could actually do this if you wanted to:
This will send the new and tload keywords, note they are separated with a colon as Basic requires. The two icons to use for downloading are send and re-send a file.
The first one is used to send a file that has not been selected yet and the second one is used to resend the selected file, this is very useful for modify - send - modify cycles.
Welcome Example
Just to give an idea of how this is used we will load the welcome.bas file (its in the downloads section).
- Set up the text transfer as above
- Type new - or use the alternative text set up
- Pick the send icon, select the welcome.bas form the open dialog and open it.
- Wait for the file to download and return to the okay prompt
You can verify that it has downloaded okay by running the program with 'go'. From a development point of view it is very easy to modify the welcome.bas file and then press the reload icon to check the results.
Loading to SD Card
The 'tload' command can also be used to load text files to the SD Card. Note tload cannot be used for binary files (see bload for that) because of the ACK arrangement and this protocol determines the end of line by either CR or LF. The syntax for loading a text file into the SD Card is:
tload to "filename.ext"
When using this method make sure that the 'Activate transfer options' in the text settings dialog is NOT checked otherwise that text will become part of the text.
The first command tload on its own will take a text file and semi-compile it into RAM, elements are added and comments are removed so that it can be understood by the Basic interpreter. Using the second form of syntax to transfer to SD Card no translation takes place and a like for like copy of the text is transfered.
Loading from SD Card
The 'load' command has been provided for loading *.bas files from the SD card to the RAM. This will only work with Basic files and translation takes place (see box). Because only basic files are allowed there is no need to specify the .bas extension. If for example a file existed on the SD Card called 'welcome.bas' then "tload welcome" would load the Basic file into ram. The 'tload' command will automatically call new before loading.
Loading Binary files
This is not really necessary as binary files can be loaded onto the SD Card from the PC, however there may be occasions when this is required via the serial USB port; i.e. without removing the SD Card.
For this command to work properly the hardware handshaking MUST be in place and BV-COM version 0.31+ should be used as this incorporates binary transfers. This can be downloaded from the downloads section.
The command is simply bload followed by the file name, for example: bload "fred.bin"
Note that you cannot 'bload' basic files into ram. The following assunes that you have 'tload'ed the 'welcome.bas' program so that the list command can be illustrated.
list ram
This should show that there are three subroutines, ‘wel_device’, ‘wel_devid’ and ‘go’. To see inside, say ‘wel_device’ type:
list ram wel_device
This will show the contents of that subroutine. Now type:
go
and run the program.