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These are the routines that turn the juice box in to a cheap serial graphics display. unix_driver.pl is an example perl unix driver program. winms_driver.pl is an example perl windows driver program.

display.c is the c program on the juicebox. Look at this program for documentation. planet571.jbp and stonehenge.jbp are sample backgrounds but any valid *.jbp can be used as a background. The ex driver displays a realtime cpu usage and memory usage on a scrolling grid as well as bargraphs. I alpha blended ts so the graphics are partially transparent. I have written all of the 12 bit color routines so you have full access to the 4096 colors(I needed them for the alpha blending).

Do the usual make -f display.mak, then load it onto the juice box example from openocd: load_binary /home/steve/juice_box/display/comm_1.bin 0x0c001000 resume 0x0c001000

or if you are one of the few with a fatjbox just put display.bin on your sd card and run.

From another terminal window run the perl driver program (note the two nonstandard modules Device::SerialPort 0 d Time::HiRes) example: ./unix_driver.pl planet571.jbp

The perl driver program supplies the data over the serial port of the pc to the juicebox. I assuming that you have a serial port attached to the juice box.

You can define bitmaps on the pc, download them over the serial port and display them on the juicebox. The barg raph and the grid are two intrinsic graphics types that the juice box display program already knows about.

Future development: I hope someone who is clever will rewrite these routines to only use the jtag port. The arm7 has a software bre ak instruction,so it is possible to watch the jtag port and wait for the display program running on the juicebo x to "break", then jtag data into a register and jtag a continue instruction. This would eliminate the costly s erial port. You can build a jtag for less than $5. Using the jtag also eliminates the need for the sd/xd hack. So you can use the juice box as a cheap graphics display for your projects like geeXboX or other HTPC.

Display.tar.gz