I'd like to reprogram just to make the interface more usable. I personally don't like the way the voltage is set by individual digits.
I'm not sure you understand that part correctly. The
granularity is variable by digit, however, it increments/decrements the next leftmost digit after 9. So you can twirl the knob from 0v to 31 volts by single volts, tenths of a volt or hundredths of a volt depending on what you need to do. Or you can go from 0 to 30 volts in 3 steps if you set the tens digit to flashing.
That said, it won't let you go past 31 volts, so if you started at 1.01v and adjusted by tens of volts, the maximum would be 21.01v. You would have to use a different granularity to go higher. If you then switched to single volts, you could go up to 30.01 volts. From there you could switch to tenths and go up to 30.91v.
I can do a little video if the above is still confusing.
For what I'm doing, I don't generally need to adjust hundredths of a volt. I just leave the hundredths digit at 0 and set the granularity at tenths (the granularity remains set unless changed). Changing the voltage is a matter of tapping the channel button once and twirling the volts dial. Similarly, tap the channel button twice and twirl the current dial.
Also, is it true that the display shows the preset voltage/current, not the actual one?
Only true until the output is turned On. Once the output is turned on, the display changes from showing the presets to showing the actual output (EXCEPT in serial mode, when the display shows 00.00 when outputs are Off and not being actively adjusted -- that's the minor bug I mentioned earlier.)
I don't want to reflash the firmware, I want to replace the whole MCU chip. Anything that is pin-compatible would fit, and there are not so many possibilities. Could you please identify the power, XTAL and SPI (to the DAC) pins?
Speak slowly and use small words! I will attempt to follow directions, but I'm an old dog trying to learn new tricks. My last quarter century was spent riding a firetruck, not sitting at an EE bench: "Me strong like bull. And smart -- Like freight train."
I'm I right that the controller board is not the same as display board? That is, could one replace the whole board leaving the original display and controls in place?
Yes, that is correct. There is a 20(?) pin header between the boards as well as a ribbon cable. The outputs are on the control board and the display/knob board sits above those in front of the control board.
[/quote]