USB-host (USB-OTG)

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Vitasam
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USB-host (USB-OTG)

Post by Vitasam » Wed Nov 06, 2019 6:06 am

Just found this external module for TI calculators.

As far as I know stm32 of DM42 can support USB-OTG. In theory, is it possible to create, e.g. USB-UART profile or something similar?
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Elektronika MK-61, Elektronika MK-52, HP15c LE, DM42 SN#16 FW 3.13

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ijabbott
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Re: USB-host (USB-OTG)

Post by ijabbott » Wed Nov 06, 2019 11:15 pm

Vitasam wrote:
Wed Nov 06, 2019 6:06 am
Just found this external module for TI calculators.

As far as I know stm32 of DM42 can support USB-OTG. In theory, is it possible to create, e.g. USB-UART profile or something similar?
I don't think the DM42 would be capable of powering any device connected to the USB port even if the chip can support OTG/Host mode. After all, it only has a crummy little CR2032 as its power source.

toml_12953
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Re: USB-host (USB-OTG)

Post by toml_12953 » Thu Nov 07, 2019 2:37 am

ijabbott wrote:
Wed Nov 06, 2019 11:15 pm
Vitasam wrote:
Wed Nov 06, 2019 6:06 am
Just found this external module for TI calculators.

As far as I know stm32 of DM42 can support USB-OTG. In theory, is it possible to create, e.g. USB-UART profile or something similar?
I don't think the DM42 would be capable of powering any device connected to the USB port even if the chip can support OTG/Host mode. After all, it only has a crummy little CR2032 as its power source.
How about a powered hub?
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DA74254
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Re: USB-host (USB-OTG)

Post by DA74254 » Thu Nov 07, 2019 7:45 pm

toml_12953 wrote:
Thu Nov 07, 2019 2:37 am
How about a powered hub?
I think that would work. At least the OTG is working towards my Android tab and phone.
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Vitasam
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Re: USB-host (USB-OTG)

Post by Vitasam » Sat Nov 09, 2019 12:29 pm

Yes, I was thinking about powered USB hub. So, basically it is the only matter of DM42 FW, HW is capable, right?
Elektronika MK-61, Elektronika MK-52, HP15c LE, DM42 SN#16 FW 3.13

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ijabbott
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Re: USB-host (USB-OTG)

Post by ijabbott » Sat Nov 09, 2019 1:11 pm

Vitasam wrote:
Sat Nov 09, 2019 12:29 pm
Yes, I was thinking about powered USB hub. So, basically it is the only matter of DM42 FW, HW is capable, right?
The STM32 chip supports OTG. I don't think the DM42 is wired up to support it. Amongst other things, it would need a high speed crystal (4-48 MHz).

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