TN207

Rabbit Cloning Board

Introduction

The Rabbit Cloning Board copies designated portions of flash memory from one Rabbit-based controller (the master controller) to another (the clone). Dynamic C version 6.50 or later is needed to use the cloning board.

Fast cloning, where the data transfer rate is the maximum allowed by the crystal frequency, was introduced in Dynamic C version 7.05. Other options were added to be used with fast cloning. In fast cloning, the size of the program to be cloned was limited by the size of the RAM, and programs that spanned two flash devices could not be cloned. The options used with fast cloning were in \lib\bioslib\fastclone.lib. For Dynamic C version 7.20 and later, the restrictions on fast cloning have been removed and fast cloning is the only implementation available or needed. Dynamic C 7.20 makes available more cloning options and all of the options can now be set using the cloning configuration macros near the top of RABBITBIOS.C in the BIOS subdirectory.

For a description of the various options, please see the section on Cloning Macros.

Key Benefits

• The Rabbit Cloning Board replaces a PC or EPROM burner as the primary tool to load programs, thus reducing costs and workspace.
• Programs may be loaded quickly onto blank, soldered on flash devices.
• High-speed data transfer at 57,600 bps or 115,200 bps.
• Higher-speed data transfer of up to 921,600 bps starting with Dynamic C version 7.05.
• Ideal for low-volume cloning production.

Steps to Enable and Set Up Cloning

Before cloning begins the master controller must be readied.

1. Connect the programming port of your master controller to a PC running Dynamic C (see Figure  1). Use the programming cable that came with the controller's Development Kit and follow the instructions in the controller user's manual.

Figure 1. Enable Cloning on Master Controller

2. Apply power to the controller.
3. Start Dynamic C and open the BIOS source code file: \BIOS\RABBITBIOS.C.
4. Change the line

   
   #define ENABLE_CLONING 0      // set to 1 to enable cloning
   

   to

   
   #define ENABLE_CLONING 1      // set to 1 to enable cloning
   

NOTE	Various options are enabled by the macros described in Cloning Macros. These macros are found in the BIOS and any change to their values must be made as part of Step 4.

5. Save the change(s) to RABBITBIOS.C and close the file.
6. Open the application program to compile to the master controller.
7. Click on the Compile to Target item in the Compile menu.
8. Remove power from the controller and disconnect the programming cable from the controller's programming port.

NOTE

If ENABLE_FAST_CLONING (available in Dynamic C versions 7.05 to 7.10 only) was set to 1 in the BIOS as part of step 4, other fast cloning options are available in \lib\bioslib\fastclone.lib. These macros are functionally the same as the macros of similar name that begin with "CL" instead of "FC" that are described in Cloning Macros. The associated macros are:

• FC_ASSUME_SAME_CRYSTAL
• FC_CHECKSUM_ENABLED
• FC_DOUBLE_CLONE_CLOCK
• FC_RUN_AFTER_COPYING

Steps to Perform Cloning

1. Use one of the cables supplied with the Rabbit Cloning Board to connect the MASTER header (J1) on the Cloning Board to the programming port of your master controller. Make sure that the colored side of the cable goes to pin 1 of the header as shown in Figure 2.

Figure 2. Cloning Cable Connections to the Rabbit Cloning Board

2. Use the other cloning cable supplied with the Rabbit Cloning Board to connect the CLONE header (J2) on the Cloning Board to the programming port of the target controller. Make sure that the colored side of the cable goes to pin 1 of the header as shown in Figure 2.
3. Apply power to both the master controller and the target controller.
4. Press the RESET MASTER button on the Rabbit Cloning Board to initiate cloning. The master begins sending the designated portion of the primary flash to the clone.

The following table describes the LED patterns that may occur on the Cloning Board.

Table 1. LED Patterns on Cloning Board

Dynamic C Version		Cloning Status
		Cloning is active	Cloning successfully completed	Error occurred
Up thru 7.06		LED blinks several times per second.	LED will blink quickly in a distinctive pattern of four flashes, then pause, then four more flashes...	LED stops blinking.
7.05 thru 7.10 in fast cloning mode		LED is off.	LED is on.	LED starts blinking.
Starting with 7.20		LED toggles on and off about once per second.	LED stays on.	LED starts blinking.

If an error occurs press the RESET MASTER button on the Cloning Board to try again.

Remove power from the target controller and unplug the cloning cable from its programming port. The master controller is now available to program the next target.

Technical Description

Figure 3 shows the Rabbit Cloning Board circuit and Figure 4 shows the programming port on a Rabbit 2000-based product. The Rabbit Cloning Board also works with Rabbit 3000-based systems.

Figure 3. Rabbit Cloning Board Circuit

Figure 4. Rabbit 2000 Programming Port

The master controller detects a connected Cloning Board when the signal CLKA is held low. This is detected in the BIOS when the reset ends and the cloning support of the BIOS is invoked. The cloning program cold-boots the target system by resetting it and downloading a primary boot program.

Since the BIOS supports a variety of flash types, the flash EPROM on the two controllers do not have to be identical. Cloning works between master and target controllers that have different-sized flash chips because the master copies its own universal flash driver to the target. The flash driver determines the particulars of the flash chip on which it is running.

The master controller's BIOS must allocate a memory buffer sufficiently large to work on the target. Prior to Dynamic C version 7.02, the cloning software used root memory for this buffer, which reduces the root memory available to the application program. The size of the buffer is given by the macro MAX_FLASH_SECTORSIZE. This macro is defined near the top of the \LIB\BIOSLIB\FLASHWR.LIB file. The default value is 1024 (4096 in older versions). The user can reduce this buffer size to the maximum of the master and target's sector sizes if root data space is a problem, or increase it to 4096 if needed.

Starting with Dynamic C version 7.02, the cloning implementation uses xmem for the buffer, so root data space will not be a problem; and no changes should be made to FLASHWR.LIB.

Cloning Macros

The following macros are in the source code of the BIOS (\BIOS\RABBITBIOS.C). The default values may be changed there. If a particular macro is not defined in the BIOS file, then the associated option is not available in the version of Dynamic C you are using. The exception to this is the fast cloning options enabled by the FC_* macros in fastclone.lib.

ENABLE_CLONING

Default is 0: cloning is not enabled. Set to 1 to enable cloning. The cloning implementation in Dynamic C version 7.10 requires that ENABLE_FAST_CLONING and ENABLE_CLONING be set to 1 to enable cloning.

CLONE_WHOLE_FLASH

Default is 0: only compiled program will be copied. Set to 1 to copy entire flash device, which excludes the system ID block unless CL_INCLUDE_ID_BLOCKS is set to 1 also. Excludes secondary flash device, but if the program being cloned extends into the second flash, it will be copied regardless of this setting.

CL_ASSUME_SAME_CRYSTAL

Default is 0: does not assume crystal speed is the same on master and clone. Set to 1 to assume same crystal speed on the master and clone, which saves code space for the crystal speed measurement and autobauding.

Autobauding works by setting the clone and master to the highest baud rate possible, and lowering the master's baud rate until they match. This MUST be set to 0 if the clone's crystal is, or might be, slower than the master's.

CL_CHECKSUM_ENABLED

Default is 0: do Internet checksum for cloning. Leaving this as 0 will save some code size and a little time. Uses RFC 1071 method.

CL_COPY_2NDFLASH

Default is 0: second flash is not cloned. Set to 1 to clone second flash. The second flash is cloned in addition to the designated area of the primary flash.

This is separate from USE_2NDFLASH_CODE so that files in the secondary flash can be copied too if desired. This will cause the whole second flash to be copied unconditionally even if the program doesn't use two flashes.

CL_DOUBLE_CLONE_CLOCK

Default is 0: If the cloned board has or might have a crystal speed more than 12.9MHz, this MUST be set to 0. This macro is independent of the CLOCK_DOUBLED macro. It only applies clock doubling WHILE cloning.

CL_INCLUDE_ID_BLOCKS

Default is 0: system ID and user block areas are not copied during cloning. Set to 1 to copy system ID and user block areas. Setting this to 1 will cause the ID blocks to be copied unconditionally.

CL_RUN_AFTER_COPYING

Default is 1: program on clone will run after cloning completes. Set to 0 to not run the program.

INITIAL_SLV_BAUD_DIV

Default is 0. If the clone is faster than, or might be faster than, the master, increase this macro to the value needed to achieve the fastest common baud rate that works on both boards. Zero will always work when the clone crystal speed is equal to the master crystal speed. (This is the value that goes in the divisor register, the actual divisor is this plus 1.)

The divisor register value is determined as follows:

For achievable baud rates, this should within 4% of an integral value. The maximum baud rate is the crystal frequency (in Hz) divided by 32. Note that if CL_DOUBLE_CLONE_CLOCK = 1, the crystal frequency is doubled in the above calculation.

STERILE_CLONES

Default is 0: cloned boards will check for the presence of a cloning cable. Set to 1 to cause cloned boards to bypass the check for the cloning cable, thereby disabling cloning of clones.

CLONINGBAUDRATE (Dynamic C versions prior to version 7.20 only)

Default is 1: baud rate is 115,200 bps. Set to 0 to use 57,600 bps. This macro is not applicable when ENABLE_FAST_CLONING is set to 1.

All controllers sold by Z-World with the Rabbit 2000^TM or the Rabbit 3000^TM chip support cloning at 115,200 bps. If you have a custom designed Rabbit-based controller with a crystal that does not support a baud rate of 115,200 bps, change this macro to zero and the baud rate will be 57,600 bps.

ENABLE_FAST_CLONING (Dynamic C versions 7.05 to 7.10 only)

Default is 0: fast cloning is not enabled. Set to 1 to enable fast cloning.

This macro was made available to speed up the cloning process, with some restrictions. See the description of the ENABLE_FAST_CLONING macro near the beginning of RABBITBIOS.C for details.

The cloning implementation in Dynamic C version 7.20 transfers data at the fastest possible speed allowed by the crystal frequency, making the ENABLE_FAST_CLONING macro unnecessary.

Summary

The Rabbit Cloning Board is an easy-to-use, inexpensive solution for low production cloning. It is fast, flexible and reliable.