Disabling reset on USB proto board
MicrocontrollerGuy
Posts: 12
Is it practical to disable the DTR reset on the Propeller USB proto board (presumably by cutting the collector trace on Q1) and yet still retain the ability to program the board when needed? In other words, is it practical to manually reset the Prop with the on-board reset button and then immediately press F11 to program it, or is there not enough of a delay in the bootloader to make this happen? I'm running into situations where the Prop is being reset at inopportune times such as due to a computer reboot, and I need the Prop to keep running during these reboots yet also remain connected to the USB port at all times.
I checked the data sheet, and on page 6, it describes the boot-up process but doesn't specify how long it waits for communication from a PC before moving on to the EEPROM. On page 30, figure 10 seems to indicate that it waits 240 ms (about 1/4 second) for communication from a PC before loading the program from EEPROM. Is that right? And it is practical in the real world to get the timing right to be able to re-program the Prop with a manual reset?
As a suggestion for future development, I'l love to see a proto board that has a reset-enable jumper that would allow DTR to pass from the FTDI chip when closed and block that signal when open. I know I could add a second FTDI USB-serial chip to the design or else just use an RS-232 level converter and serial port, but I'd really like to use the built-in USB port if possible.
I checked the data sheet, and on page 6, it describes the boot-up process but doesn't specify how long it waits for communication from a PC before moving on to the EEPROM. On page 30, figure 10 seems to indicate that it waits 240 ms (about 1/4 second) for communication from a PC before loading the program from EEPROM. Is that right? And it is practical in the real world to get the timing right to be able to re-program the Prop with a manual reset?
As a suggestion for future development, I'l love to see a proto board that has a reset-enable jumper that would allow DTR to pass from the FTDI chip when closed and block that signal when open. I know I could add a second FTDI USB-serial chip to the design or else just use an RS-232 level converter and serial port, but I'd really like to use the built-in USB port if possible.
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