Serial Backpack questions - and problems

Hi folks;

I picked up two of the serial backpacks and have run into some problems…

First one is that it apparently is locked at 9600 bps. This is kind of a problem in a few cases, most particularly with the ZX processor - its serial-defined channels can have their timing subtly disruprted by things that disable interrupts (e.g. sync I/O) and as such lower baud rates are better. Ideal would be 2400… I can probably get around this, although I might have to do some kinda wild stuff to do so on one of my projects…

Second, and potentially a show-stopper, is that the backlight control doesn’t work right. The documentation says that 124 + a byte from 128 - 157 control the PWM control, with 128 being off and 157 being “full”. All work fine EXCEPT 128 - that returns “full on” instead of “off”. Oops. Since I NEED soft backlight control to get a handle on power consumption this is a big deal.

Any ideas? Other than that it appears to be working… The lack of soft baud control is a bit disappointing though - that would be awesome if it was/could be supported.

I agree. We need to revisit this design and see about adding the alternate baud rates with better PWM control of the backlight.

For the time being, the backlight can be set to 129 instead of 128. The current consumption will be nearly 0.

-Nathan