DM42 : What a beauty !

Discussion around the Swiss Micros DM42 calculator.
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Vitasam
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USB OTG ?

Post by Vitasam » Thu Oct 25, 2018 4:47 am

According to ST datasheet, devices do support USB OTG:

Code: Select all

USB OTG 2.0 full-speed, LPM and BCD
Am I correct that, in theory, DM42 can act as an USB host? So one can plug e.g. usb-2-uart adapter if needed SW support will be done to DM42 firmware?
Elektronika MK-61, Elektronika MK-52, HP15c LE, DM42 SN#16 FW 3.11

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ijabbott
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Re: USB OTG ?

Post by ijabbott » Thu Oct 25, 2018 6:22 am

Vitasam wrote:
Thu Oct 25, 2018 4:47 am
According to ST datasheet, devices do support USB OTG:

Code: Select all

USB OTG 2.0 full-speed, LPM and BCD
Am I correct that, in theory, DM42 can act as an USB host? So one can plug e.g. usb-2-uart adapter if needed SW support will be done to DM42 firmware?
Perhaps, but it wouldn't be able to supply any power to the USB device.

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Vitasam
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Re: USB OTG ?

Post by Vitasam » Thu Oct 25, 2018 8:20 am

ijabbott wrote:
Thu Oct 25, 2018 6:22 am
Vitasam wrote:
Thu Oct 25, 2018 4:47 am
According to ST datasheet, devices do support USB OTG:

Code: Select all

USB OTG 2.0 full-speed, LPM and BCD
Am I correct that, in theory, DM42 can act as an USB host? So one can plug e.g. usb-2-uart adapter if needed SW support will be done to DM42 firmware?
Perhaps, but it wouldn't be able to supply any power to the USB device.
Yes, but form-factor of that USB-otg device may look like this with additional AAA batteries.
Elektronika MK-61, Elektronika MK-52, HP15c LE, DM42 SN#16 FW 3.11

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Vitasam
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Re: DM42 : What a beauty !

Post by Vitasam » Wed Nov 07, 2018 12:00 pm

Here is the NumWorks calculator is controlling a modified elegoo rover over a serial port.
The calculator is connected to robot with the USB cable, but not using the USB protocol. The data lines of the USB port are remapped to an uart by the firmware.

Could be a very useful feature (if it doable) for DM42 too.
Elektronika MK-61, Elektronika MK-52, HP15c LE, DM42 SN#16 FW 3.11

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ijabbott
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Re: DM42 : What a beauty !

Post by ijabbott » Thu Nov 08, 2018 5:44 pm

Vitasam wrote:
Wed Nov 07, 2018 12:00 pm
Here is the NumWorks calculator is controlling a modified elegoo rover over a serial port.
The calculator is connected to robot with the USB cable, but not using the USB protocol. The data lines of the USB port are remapped to an uart by the firmware.

Could be a very useful feature (if it doable) for DM42 too.
I don't think it's doable for DM42 because the USB data pins are not multiplexed with any UART TX or RX pins on the STM32L476RG. They are multiplexed with the CAN bus controller, so perhaps that's an option.

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