NP-41 Emulator (may be)

[Chris Chung]

I hope every owner had either received their unit and have them working, or have their issues being addressed by myself.

If you have USB-Serial dongle, Loading 2 ROMS (on two slots) always results in the 2nd one not working / showing up on "CAT 2". You will need to erase 1 of them afterwards. You may try different ROMS, slots and provide feedback to me as I am very in-experience w/ the working of the ROM modules.

If you had succeeded w/ ROM loading, you can try the bootloader to upgrade your firmware. Over the weekend I tried it and found it to be robust. I try to mess it up by sending garbage, ascii mode instead of binary mode on the firmware, etc. And of course it failed to load. But the bootloader was still intact and can accept another try.

The design is a very small / simple bootloader set aside in memory far away (from the firmware). And subsequent firmware updates do not touch the bootloader code space.

The latest firmware has only one small change, it allows a ON-TAN key sequence during cold start / key test mode and this will clear the 4 ROM memory sections.

Please try it if you have a reliable USB-Serial setup and a experimental mind.

(12-15-2017 08:24 PM)anetzer Wrote:  

(12-12-2017 11:22 PM)Didier Lachieze Wrote:  I love this LCD display !

So do I, but I am obviously by now completely lost between the existing options:

Hiw does one get to order one with this fabulous segment display?!

Plus: I get the impression that the current badge is rather beta stage. Will there be a formal notification, when the problems are ironed out and what options will be acailable then?

Thank you for any info!

a

The LCDs were custom made for the NP41 project. I am actually reluctant to sell them. A lot of effort was made to realize this, not to mention that I was lucky to meet the right / kind people to help me out. There were a lot of proxy / relay on the design, prototyping, production, payment, shipping, custom clearing, etc. I doubt I will want to do that often.

The few pieces I sold I didn't put much thought as it's a fellow member doing his similar project and wants them. I am getting PMs for more LCDs. I am going to be selective and only offer them to active members who will be using it in concrete projects.

If you want 1 or 2, please at least show your project framework (how are you going to drive them, which MCU are going to be used, etc) as I only want them to be utilized properly.

Yes, we are experiencing quite a bit of intermittent H/W issues in this batch. Until I can iron this out, I really don't want to rush into a second batch as it will benefit no one.

(12-16-2017 07:51 PM)Egan Ford Wrote:  Mine arrived yesterday. Thanks! I have not had any issues that I am aware of. Everything worked as expected. All keys good, etc...

Questions/comments:

1. When I press PROG I get 00 REG 46, shouldn't the CV report 00 REG 319? Or is this a C? I may have missed something in the previous threads. EDIT: NM forgot about SIZE.

2. I didn't have any problems getting to the serial menu at 9600 using GNU Screen from my Mac, however I have not tried to do anything like upload a ROM yet. I'll need something other than screen to do that. I may write something custom for that.

3. The 3d printed case is a very nice touch. Easy access to back and front.

4. Suggestion. If possible consider the staggered header holes that the pocket chip uses (e.g. https://cdn.shopify.com/s/files/1/1065/9...5947226880). This will allow header pins to be snugly connected. However I didn't have any problems dropping a 4-ping header in there and using the tension of the jumper wires to hold it firm.

5. I used this for the USB to serial: https://www.amazon.com/gp/product/B019I3CAIE. I use these for other embedded and SBC use. The pic is wrong in that link however. Its the correct size but has FTDI vs PL2303. It also ships with headers and jumper wires. Everything you need.

6. The build quality IMHO is spectacular.

7. What are the other non-serial headers for?

Thanks again.

Thanks for your comment / review.

2. I don't use IOS, I guess it will be similar to Linux, may be cp to the raw device. If you succeed w/ method or utilities, please post it here.

3. Yes, I want something simple and easy to produce, still it requires almost 2 hr for my slow 3D printer to do one. I am working on some kind of protection for the LCD before I let my kids to bring one to school.

4. I will look into that, the PCB designer I used (Fritzing) is quite limited but there are always ways to work-around.

5. Yes, some of my older USB-Serial also works, they work if you PC OS sees them. We need 3.3V though, I now see there are many offers in amazon and shipping is quick, some w/ jumpers already, just need a few header pins to get them going.

6. They are far from that. I do now get a hang of it. The ordered PCB is pre-tinned. I actually will not add solder to the pad. I now position the chip and use my solder iron to secure the corners, and then use hot air gun + flux to reflow.

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.

7. They are unused I/Os (some with ADC / I2C / Uart and other capabilities) that I just draw them out. There are also a 4-pin block for native TI programmers to flash firmware. It allows possibilities like device network, printer, IR, etc. And I don't have knowledge on them (i.e. HP devices).