Dynamic Web Pages
[HTTP Server]

Introduction

The HTTP Server can dynamically alter pages and substitute real-time information, such as input/output status. The web server will parse CGI files for special tags, and replace them with user defined string. Only "*.cgi" files are parsed for these special tags.

To incorporate this real-time information, the corresponding CGI file (*.cgi) must contain a text string with the format: "%nxx". Where the '%' character serves as a control code, 'n' represents the variable group and "xx" represents a two-digit variable value ( in uper case hex format).
The variable value has a range of 00-FF (Which translates to 0-255 decimal), and must use upper case characters!
The variable group ('n' character) can be any alpha numeric character ('0-9', 'a-z', 'A-Z'), giving a total of 10+26+26 = 62 groups. Each group can have 256 variable values. This gives a total of 15872 possible variables.

When the HTTP Server encounters this text string, it removes the '%' character and calls the HTTPGetVar() function. This function has been implemented by the Modtronix SBC68EC Web Server in the "httpexec.c" file! All tags implemented by the Modtronix SBC68EC Web Server are listed below.

The HTTPGetVar() function will define strings that will replace tags found in the "*.cgi" file. If the page requires '%' as a display character, it should be preceded by another '%' character. For example, to display "23%" in a page, put "23%%".

Defined Tags

The following list of tags are implemented by the Modtronix SBC68EC Web Server in the "httpexec.c" file. This file can be modified by the user to add aditional tags:

Variable group n - Analog Inputs
Variable group k - Configuration Values
Variable group l - General
Variable group a to j - PIC Ports

PIC Ports

The variable groups a to j can be used to display the value of any input pin or port on the PIC. The lower 3 bits of the 8 bit variable value is used to specify the desired bit of the given port (port is given by variable group). The upper 5 bits are used to specify how the ports value should be displayed. The following variable groups are defined:

Variable Group	Description
a	PIC Port A
b	PIC Port B
c	PIC Port C
d	PIC Port D
e	PIC Port E
f	PIC Port F
g	PIC Port G
h	Reserved for furture use
j	Reserved for furture use

The following variable values(in hex) are defined:

Variable Value String returned by HTTP Server - displayed on web page

00 - 07 '1' or '0' returned depending on PORT state

10 - 17 "on" or "off" returned depending on PORT state

20 - 27 "" returned if port is configured as input

30 - 37 "" returned if port is configured as output

40 - 47 "checked" returned if port is configured as output

48 - 4f "checked" returned if port is configured as input

50 - 57 "0" returned if port is configured as output. "1" returned if port is configured as input.

For variable values where bit 3 is set (values from x8 to xf):
x8=port bit 0, x9=port bit 1, xa=port bit 2, xb=port bit 3
xc=port bit 4, xd=port bit 5, xe=port bit 6, xf=port bit 8
For example, variable value 48 will return "checked" if port bit 0 is configured as an input

Examples:

Example Tag Description

%a02 Variable group = a, Variable value = 0x02. This example will display the value of port A2 as '1' or '0'. So, if port A2 is set, a '1' will be displayed on the web page in stead of '%a02'

%c17 Variable group = c, Variable value = 0x17. This example will display the value of port C7 as 'on' or 'off'. So, if port C7 is clear for example, 'off' will be displayed on the web page in stead of '%c17'

%f22 Variable group = f, Variable value = 0x22. Variable values 20 to 2F can be used to place HTML comments around HTML code if a port is configured as an input. For example, to only display an image if a Port pin RF1 is configured as an output, you could write:
%f21<img src="picture.jpg">%f29

%g52 Variable group = g, Variable value = 0x52. This example will display '1' if port G2 is configured as an input, and '0' if port G2 is configured as an output.

%b45 Variable group = b, Variable value = 0x45. This example will display 'checked' if port B5 is configured as an output.

%c4c Variable group = c, Variable value = 0x4c. This example will display 'checked' if port C5 is configured as an intput.

Analog Inputs

The variable group n can be used to display the value of any Analog Input on the PIC.

The following variable values(in hex) are defined:

Variable Value String returned by HTTP Server - displayed on web page

00 - 0A 2 or 3 digit hex value in capital letters

10 - 1A Decimal value 0 - 255 or 0 - 1023

20 - 2A Decimale value, 2 decimal places for 5V reference

30 - 3A "" returned if the channels is configured for ADC

50 - 5A "" returned if the channels is NOT configured for ADC

Examples:

Example Tag Description

%n02 Variable group = n, Variable value = 0x02. This example will display the value of Analog Input 2 in uppercase hex. For example, "A8" will be displayed on the web page in stead of '%n02' if Analog Input 2 has the value 0xA8.

%n1A Variable group = n, Variable value = 0xaA. This example will display the value of Analog input 10 in decimal. For example, "210" will be displayed on the web page in stead of '%n1A' if Analog Input 10 has the value 210.

%n32 Variable group = n, Variable value = 0x32. Variable values 30-3A and 40-4A can be used to place HTML comments around HTML code if a PIC port pin is configured as an Analog Input. For example, to only display an image if a Analog Input 2 is configured as an Analog Input, you could write:
%n32<img src="picture.jpg">%n42

General

The variable group l is used for displaying general information.

The following variable values(in hex) are defined. If the Logged In column contains a 'X' character then this tag will only be parsed if the current user is logged in!

Variable Value Logged In String returned by HTTP Server - displayed on web page

00 Displays the Username of the current user. For example "Guest" or "Admin". The current user will be "Guest" if the user has not logged in.

01 Displays the TCP/IP stack version. For example "V2.04".

02 Displays the Application version. For example "V3.00".

03 Returns '0' if we are currently not logged in, or '1' if we are.

04 Displays 'Yes' if the board has a bootloader, else 'No'

05 Displays our NetBIOS name

10 Displays first part of current IP address. For example, will be '5' if our IP is '10.1.0.5'.

11 Displays second part of current IP address.

12 Displays third part of current IP address.

13 Displays fourth part of current IP address. For example, will be '10' if our IP is '10.1.0.5'.

14 Displays first part of MAC address. For example, will be '5' if our MAC is '0.1.2.3.4.5'.

15 Displays second part of MAC address.

16 Displays third part of MAC address.

17 Displays fourth part of MAC address.

18 Displays fifth part of MAC address.

19 Displays sixth part of MAC address. For example, will be '200' if our MAC is '200.1.2.3.4.5'.

1A Displays first part of current Network MASK. For example, will be '255' if our mask is '0.0.0.255'.

1B Displays second part of current Network MASK.

1C Displays third part of current Network MASK.

1D Displays fourth part of current Network MASK. For example, will be '15' if our mask is '15.0.0.255'.

1E Displays first part of current Gateway address. For example, will be '5' if our Gateway Address is '10.1.0.5'.

1F Displays second part of current Gateway address.

20 Displays third part of current Gateway address.

21 Displays fourth part of current Gateway address. For example, will be '10' for '10.1.0.5'.

Examples:

Example Tag Description

%l00 Variable group = l, Variable value = 00. This example will display the name of the user currently logged in. If the username of the user currently logged in is "Admin", then "Admin" will be displayed on the web page in stead of '%l00'

%l10.%l11.%l12.%l13 Variable group = l, Variable value = 10 to 13. This example will display our IP address.

Configuration Values

The variable group k is used for displaying the contents of the Application Configuration bytes. The values are displayed in decimal! The variable value (in uppercase hex) is used to specify the offset of the configuration byte to display. All of these tags are only parsed if the current user is logged in!

Examples:

Example Tag Description

%k00.%k01.%k02.%k03 This example will display the currently configured IP address. If the IP address is "10.1.0.1", then "10.1.0.1" will be displayed on the web page in stead of "%k00.%k01.%k02.%k03".

%k0A.%k0B.%k0C.%k0D This example will display the currently configured network MASK. If the MASK is "255.0.0.0", then "255.0.0.0" will be displayed on the web page in stead of "%k0A.%k0B.%k0C.%k0D".

Generated on Mon Oct 9 11:35:15 2006 for SBC68EC Web Server by

1.4.7

Variable Value	String returned by HTTP Server - displayed on web page
`00 - 07`	'1' or '0' returned depending on PORT state
`10 - 17`	"on" or "off" returned depending on PORT state
`20 - 27`	"<!--" returned if port is configured as input
`28 - 2f`	"-->" returned if port is configured as input
`30 - 37`	"<!--" returned if port is configured as output
`38 - 3f`	"-->" returned if port is configured as output
`40 - 47`	"checked" returned if port is configured as output
`48 - 4f`	"checked" returned if port is configured as input
`50 - 57`	"0" returned if port is configured as output. "1" returned if port is configured as input.

Example Tag	Description
`%a02`	Variable group = a, Variable value = 0x02. This example will display the value of port A2 as '1' or '0'. So, if port A2 is set, a '1' will be displayed on the web page in stead of '%a02'
`%c17`	Variable group = c, Variable value = 0x17. This example will display the value of port C7 as 'on' or 'off'. So, if port C7 is clear for example, 'off' will be displayed on the web page in stead of '%c17'
`%f22`	Variable group = f, Variable value = 0x22. Variable values 20 to 2F can be used to place HTML comments around HTML code if a port is configured as an input. For example, to only display an image if a Port pin RF1 is configured as an output, you could write: %f21<img src="picture.jpg">%f29
`%g52`	Variable group = g, Variable value = 0x52. This example will display '1' if port G2 is configured as an input, and '0' if port G2 is configured as an output.
`%b45`	Variable group = b, Variable value = 0x45. This example will display 'checked' if port B5 is configured as an output.
`%c4c`	Variable group = c, Variable value = 0x4c. This example will display 'checked' if port C5 is configured as an intput.

Variable Value	String returned by HTTP Server - displayed on web page
`00 - 0A`	2 or 3 digit hex value in capital letters
`10 - 1A`	Decimal value 0 - 255 or 0 - 1023
`20 - 2A`	Decimale value, 2 decimal places for 5V reference
`30 - 3A`	"<!--" returned if the channels is configured for ADC
`40 - 4A`	"-->" returned if the channels is configured for ADC
`50 - 5A`	"<!--" returned if the channels is NOT configured for ADC
`60 - 6A`	"-->" returned if the channels is NOT configured for ADC

Example Tag	Description
`%n02`	Variable group = n, Variable value = 0x02. This example will display the value of Analog Input 2 in uppercase hex. For example, "A8" will be displayed on the web page in stead of '%n02' if Analog Input 2 has the value 0xA8.
`%n1A`	Variable group = n, Variable value = 0xaA. This example will display the value of Analog input 10 in decimal. For example, "210" will be displayed on the web page in stead of '%n1A' if Analog Input 10 has the value 210.
`%n32`	Variable group = n, Variable value = 0x32. Variable values 30-3A and 40-4A can be used to place HTML comments around HTML code if a PIC port pin is configured as an Analog Input. For example, to only display an image if a Analog Input 2 is configured as an Analog Input, you could write: %n32<img src="picture.jpg">%n42

Variable Value	Logged In	String returned by HTTP Server - displayed on web page
`00`		Displays the Username of the current user. For example "Guest" or "Admin". The current user will be "Guest" if the user has not logged in.
`01`		Displays the TCP/IP stack version. For example "V2.04".
`02`		Displays the Application version. For example "V3.00".
`03`		Returns '0' if we are currently not logged in, or '1' if we are.
`04`		Displays 'Yes' if the board has a bootloader, else 'No'
`05`		Displays our NetBIOS name
`10`		Displays first part of current IP address. For example, will be '5' if our IP is '10.1.0.5'.
`11`		Displays second part of current IP address.
`12`		Displays third part of current IP address.
`13`		Displays fourth part of current IP address. For example, will be '10' if our IP is '10.1.0.5'.
`14`		Displays first part of MAC address. For example, will be '5' if our MAC is '0.1.2.3.4.5'.
`15`		Displays second part of MAC address.
`16`		Displays third part of MAC address.
`17`		Displays fourth part of MAC address.
`18`		Displays fifth part of MAC address.
`19`		Displays sixth part of MAC address. For example, will be '200' if our MAC is '200.1.2.3.4.5'.
`1A`		Displays first part of current Network MASK. For example, will be '255' if our mask is '0.0.0.255'.
`1B`		Displays second part of current Network MASK.
`1C`		Displays third part of current Network MASK.
`1D`		Displays fourth part of current Network MASK. For example, will be '15' if our mask is '15.0.0.255'.
`1E`		Displays first part of current Gateway address. For example, will be '5' if our Gateway Address is '10.1.0.5'.
`1F`		Displays second part of current Gateway address.
`20`		Displays third part of current Gateway address.
`21`		Displays fourth part of current Gateway address. For example, will be '10' for '10.1.0.5'.

Example Tag	Description
`%l00`	Variable group = l, Variable value = 00. This example will display the name of the user currently logged in. If the username of the user currently logged in is "Admin", then "Admin" will be displayed on the web page in stead of '%l00'
`%l10.%l11.%l12.%l13`	Variable group = l, Variable value = 10 to 13. This example will display our IP address.

Example Tag	Description
`%k00.%k01.%k02.%k03`	This example will display the currently configured IP address. If the IP address is "10.1.0.1", then "10.1.0.1" will be displayed on the web page in stead of "%k00.%k01.%k02.%k03".
`%k0A.%k0B.%k0C.%k0D`	This example will display the currently configured network MASK. If the MASK is "255.0.0.0", then "255.0.0.0" will be displayed on the web page in stead of "%k0A.%k0B.%k0C.%k0D".