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P2 Maxi Breakout Board - Page 2 — Parallax Forums

P2 Maxi Breakout Board

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  • hinvhinv Posts: 1,255

    @msrobots said:
    please do NOT make the mistake again attaching a FTDI to each board. Please.

    PropPlugs are easy and can be removed to use the pins without FTDI from other MCs.
    Parallax did the move after the P1 Project board and it is a PITA to cut out or de-solder the FTDI on most parallax boards.

    Other than cost for the FTDI chip in particular, why not put a USB2serial capable chip on board?
    I really loved the Propeller Proto USB boards, and I have lost my tiny little prop plug several times.
    I also find it annoying to have to hunt down or carry a power supply if I just want to program the chip without high power drains on the pins.

    Doug

  • Yes, I am still very much thinking, that an attractively priced board would be very good, that includes everything needed to start: Usb power supply, Usb-serial, bread board friendly connectors, SD slot.
    P2 is just way too expensive, if you add up the expensive module + adaptor + Usb serial. (And I don't know for whom a module is convenient, that sticks out 90 degrees from the adaptor blowing up the enclosure?)

  • pik33pik33 Posts: 2,387

    sticks out 90 degrees

    That's why there are angular edge slots. We use them in our robots: the Edge is horozontal and fastened to the main board with 2 screws using these 2 holes on the top.

  • @"Christof Eb." said:
    Yes, I am still very much thinking, that an attractively priced board would be very good, that includes everything needed to start: Usb power supply, Usb-serial, bread board friendly connectors, SD slot.
    P2 is just way too expensive, if you add up the expensive module + adaptor + Usb serial. (And I don't know for whom a module is convenient, that sticks out 90 degrees from the adaptor blowing up the enclosure?)

    I do not use breadboard at all but doesn't KISS0001 check almost all the boxes ?

    • atractively priced (impossibly cheap) - check
    • excellent quality - check
    • USB powered - check
    • 2,54 mm spaced connectors - check (maybe not 100% compatible with internal breadboard wiring, I'm not sure but very easy to overcome this inconvenience)
    • SD card slot - check
    • usb-serial - no check (and I would like to keep this as it is. Almost every person even remotely having to do with microcontrollers already has some sort of usb-serial converter at hand, most probably in variants).

    Other than that I can see your point and agree with you and if such "KISS like" board existed with the usb to serial already on board I would buy (more than) one on the spot as well.

    If it also had a power backed up RTC and a VGA connector and maybe a PS2 connectors on board, external RAM ... But I'm very happy with the KISS board as it is.

  • I use the 90 degree Edge slot on my Light controller. Makes it as tall as the powersupply mounted above it, easy access to the SD slot, and saved on board space. I like the Edge form factor.

  • hinvhinv Posts: 1,255

    @VonSzarvas
    Just now reviewing the Dec 15th Propeller Live video. It looks like you really tightened up the dimensions since that picture. That is much appreciated.

  • jmgjmg Posts: 15,175

    @hinv said:
    Why not fit for these?
    https://www.tindie.com/products/invector/challenger-rp2040-mstk/
    Then you get an RP2040, which would have to be programmed to store and boot the P2, but you also get battery connection too. The blank space on the top means that you can surface mount underneate, or upside down on top. I hate paying for FTDI chips, which are pretty simple. The RP2040 is WAY more capable for about the same price as an FTDI module.

    What is the practical MAX baud a PICO can manage ? DOCs give MAX = 921600 ?

    The Pi DOCs say this
    // PICO_CONFIG: PICO_DEFAULT_UART_BAUD_RATE, Define the default UART baudrate, max=921600, default=115200, group=hardware_uart

    The PICO is also only FS-USB, so has the 12MHz limit of FS-USB as a hard limit.

    I've tested these CH347 HS-USB UART Bridge boards to 9MBd duplex, and they seem almost as good as the more expensive FT232H/FT2232H parts.
    https://www.aliexpress.com/item/1005004685449797.html

  • hinvhinv Posts: 1,255
    edited 2023-01-14 01:11

    I've tested these CH347 HS-USB UART Bridge boards to 9MBd duplex, and they seem almost as good as the more expensive FT232H/FT2232H parts.
    https://www.aliexpress.com/item/1005004685449797.html

    Very nice. How much power can they deliver? I would love to have a single USB cable going to a P2 for programming.

  • jmgjmg Posts: 15,175

    @hinv said:

    I've tested these CH347 HS-USB UART Bridge boards to 9MBd duplex, and they seem almost as good as the more expensive FT232H/FT2232H parts.

    Very nice. How much power can the deliver? I would love to have a single USB cable going to a P2 for programming.

    Interesting question. I think those WCH USB Bridge parts / modules default to the standard USB settings, which means 500mA max at 5V.

    WCH do have parts like CH224K that support the USB power delivery options of higher bus voltages, (up to 100W there) for those you would need compatible power sources and suitable SMPS.
    For P2, you may not need 20V and 5A

    I find these notes, which suggest you might get to 3A / 5V with a compatible USB connection.

    And WCH parts come as small as SOT-26, with comments like

    7.4. CC1/CC2/DP/DM pins
    CC1/CC2 pins are used for device access detection and PD protocol handshake, CH235S/CH231K supports DFP mode defined by Type-C protocol Type 500mA, 1.5A or 3A current broadcast.
    The DP/DM pin is used for BC1.2 and other related protocol handshaking, and it is only provided on CH235S.

    The more expensive FTDI part may offer some options

    FT233HPQ
    This Hi-Speed USB device with Type-C/PD 3.0 controller IC fully supports the latest USB Type-C and Power Delivery (PD) standards enabling support for power negotiation with the ability to sink or source current to a USB host device.
    This has one Dual-role PD port (PD port 1) which also carries the USB data communication. This can switch between the roles of sinking power from the host to power the peripheral, and sourcing power to charge the host computer.
    A second included PD port (PD port 2) is a power sink and can be used to connect an external power source/charger. This can provide power to the peripheral board as well as charging the host via PD port 1.

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