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Posts: 2,222 | Thanked: 12,651 times | Joined on Mar 2010 @ SOL 3
#2600
Originally Posted by teroyk View Post
I have some questions before I make my order:
1. I am not sure is this right way to calculate R&D cost, 160 kEUR / 500=320 EUR. Yes you can get payment for R&D, but I think you should believe that you can sell at least 1000. And you sell that much if prices are about 150 euros less. Because I have add 24% VAT so the total cost is much more than 990 euros to me. Or can I calculate with German VAT if I buy it in EU?
2. And more important question to me, Can that UART console connector use with 31250 baud rate? Is there low level documentation about it somewhere?
For the R&D cost calculation please see Werner's http://neo900.org/estimate - we can't make assumptions based on belief, we need to oparate on hard numbers, with a strategy how to act on all possible outcomes. Regarding VAT please bear with us, this is our very first shop and we haven't sold a single item yet. So sorting out any tax issues is a pending topic and I can't say anything binding regarding that, except "I need to ask my tax adviser".

Regarding the UART: yes it should operate on the 38kbd range, without any problems. It's a pretty normal UART. I can't tell about particularly 31250 baud rate without checking back in TRM of DM3730, it sounds a tad odd and I don't know if the UART clock supports this precise unusual non-power2 frequency. For low level documentation please see "Hackerbus" on http://neo900.org/resources as well as schematics, IR-whitepaper and the DM3730 TRM (refer to "Blockdiagram" in http://neo900.org/resources)

cheers
jOERG

[edit]
Oh, I just realized that 31250 baud is MIDI. Well, that should be quite usual then and supported by almost all UARTs
So here's the relevant quote from SWPU223M:
The UARTs (UART1, UART2, and UART3 when in UART mode) include the following key features:
• 16C750 compatibility
• 64-byte FIFO for receiver and 64-byte FIFO for transmitter
• Programmable interrupt trigger levels for FIFOs
• Baud generation based on programmable divisors N (N = 1...16,384) operating from a fixed functional
clock of 48 MHz
Oversampling is programmed by software as 16 or 13; thus, the baud rate computation is either:
• Baud rate = (functional clock/16)/N
• Baud rate = (functional clock/13)/N
48Mhz/16/96=31250

Last edited by joerg_rw; 2015-06-04 at 06:08.
 

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