NP-41 Emulator (may be)

[Chris Chung]

+Sylvia,
I had shipped your replacement unit yesterday, you should be receiving it tomorrow Thursday.

(12-18-2017 07:32 PM)Guenter Schink Wrote:  Hi Chris,
received my unit, thank you. There is an odd behaviour with ATAN, ASIN and ACOS: for most values the calculater will just show the command and then freeze. Switching it off and on, again shows the command, still frozen. Switching it off and doing a "Memory lost" brings it back to life.

Günter

Edit: Key test "x" toggles between all segments dimmed plus K=41 and then K=41 only. "R/S" shows all zeros first second push K=48

Hi Guenter,
Sorry you also got a lemon. It appears your firmware / register memory got messed up and that the "Memory Lost" is not fixing it (perhaps outside emulator scope). Similar to what Sylvain is experiencing. I did manage to reproduce this condition and is not yet able to find out why. And it could be reset by re-flashing the firmware via bootloader.
But of course if we don't know the cause of it, this is not a solution.
I had ran out of replacement units and had made a new unit yesterday. Although it appears good, I am losing confidence with the builds and I will test / use it for a week before shipping the replacement to you.

(12-18-2017 06:21 PM)hth Wrote:  

(12-18-2017 02:50 PM)Chris Chung Wrote:  The issue I have now is that the H/W reset itself intermittently. I think I will need to invest in a scope to pinpoint things in more detail. It could be ESD, will put ground shields on next PCBs and see. This problem is running around and difficult to chase.

A long shot, double check the watchdog. This is a common source of problems with MSP430.

Håkan

Yes, I am reading the datasheet / user guide in depth. There should be registers to catch the source of reset and I will have to see if it will be useful for the investigation or not. I think I disable the watchdog timer (which I usually do as a lazy programmer). Will have to change that.

The FRAM family is relatively new, not sure if it is the way I am reading / writing to them, there are certain timing / voltage requirements for writes.

For this project, I can find a good substitute for the MSP430 though. It got in-build high segment count LCD driver, FRAM memory, sleeps at 0.6uA, all in one chip. Substituting w/ a few other chips will introduce other problems. So I will stick to debugging this.