Nothing from MS again.
I looked at the schematic for the ZL70550 and it looked like it required a lot of extra parts that had to be placed just right.
I assume that the ZL70550 has a lot of overlap with the ZL70251
which they seem less paranoid about. I looked at the programmer documentation and I have waves of Nanotron nausea sweeping over me. The setup and calibration process goes on for 22(sic) pages. The chances that I can get the ‘550 to work using just the ‘251 documentation seems remote. Indeed the chance that I can get the ‘251 to work without working firmware to which I can refer is even less. Unless they provide documentation and sources, I think trying to mount these chips on our board is almost a waste of time.
I can see that the eval kit would be quite valuable for debugging, but I don’t think you actually get sources with that either.
The radio is such a bleeding prima donna to set up and use that MicroSemi are going to have a lot of trouble selling any until they make it shitload easier – like providing a module with a much simpler interface.
So what to do?
- Make an nRF52 board anyway, and hope the ZL70550 software comes through
- Choose a different, less efficient WUP radio, and make a generic WUP API so it is easy to upgrade
- Continue using the 2 x Nordic nRF52 boards with wires jumpered to the TS06.2, and use BLE for WUP
- As (3) but make a TS shield for the Nordic nRF52 eval boards with DW etc
On Wed, Jun 8, 2016 at 9:36 PM, Mik Lamming <email@example.com>
I should probably give them a few more days, and then bug Jean-Luc again.
On Wed, Jun 8, 2016 at 7:44 PM, David Carkeek <firstname.lastname@example.org>
They probably feel like they can’t be bothered supporting a hobbyist who just going to ask for free parts and suck up resources. Therefore you’ll have to make yourself such a pest they’ll give you what you want just to make the whine go away. Do you want to introduce me to them so I can start being a pest?
If one of the requirements for the next board is to accept a standard Arduino shield then it can’t be a “small” board, such as TS05/6. Therefore TS07.1 could have footprints for everything on it we are considering; each section can have jumpers for connecting to UART/SPI/I2C. So we can put on both the ZL70550 and ZL70251, plus all the IMU components, and the uSD card socket.
Perhaps it’s not important to have the ZL70550 to validate the concept of using an ISM 800MHz radio. Maybe one of the TI solutions is worth looking at. Or what about the Nordic nRF905? After it is proven to be a win then the ZL70550 can be used to reduce power. Or is there something special about the ZL70550 implementation?
But it would suck to have to rewrite a bunch of code. On the other hand using a mature product will probably be easier so in the end the total effort might not be more.
IMO accepting an Arduino shield isn’t a requirement – it’s more a possible short-cut to avoid having to layout a full board. I keep suggesting it in the probably mistaken hope that it might be less work than doing a full board, PSU and all that stuff.
I don’t think there is anything special about the MicroSemi chips other than their very low listen power. Any 800MHz radio will have better range than the 2.4GHz BLE for the same power level if Friis is to be believed. I don’t need any of the clever stuff – just the ability to send a peer address, and checksum.
The nRF52 listen current is 5.5mA, but the packets are 256 bytes + preamble
The nRF905 is an 8085 chip (assembler progamming) darws 12.4mA in RX
Using the ZL70550 offers 2.4mA, but the range may be better, and I can use very short packets. But there is always a substantial preamble, and the packet length savings might not add much. So I see the power win not being worse than 2x, and not better than 5x compared to BLE. It certainly isn’t worth toughing it out to get the ZL chip working with no help from MicroSemi.
I should just plow on and try to make the BLE version work well enough to figure out if it is a dead dog. If it works then we can revisit an ISM radio.