Trouble getting started on GPy

[helltoupee]

Hello everyone,

I jut purchased a GPy module and have been trying to connect for the first time. I have an FTDI serial converter attached to the Tx/Rx pins and when I power on the module I can see some signs of life over the serial port and the LED shows red. Putty shows the following:

▒ets Jun  8 2016 00:22:57

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff9028,len:8
load:0x3fff9030,len:1076
load:0x4009fa00,len:0
ho 12 tail 0 room 4
load:0x4009fa00,len:15344
entry 0x400a070c

However, this seems to be as far as it goes. it echoes characters I type back, but otherwise seems unresponsive to either Pymakr or anything else. I saw a post on the forums about the red LED possibly indicating the firmware needs to be updated, so I downloaded the firmware update tool and gave that a shot, but unfortunately keep receiving a "Timed out while waiting for packet header" error.

When grounding P2, the module does appear to enter the bootloader properly:

ets Jun  8 2016 00:22:57

rst:0x1 (POWERON_RESET),boot:0x3 (DOWNLOAD_BOOT(UART0/UART1/SDIO_REI_REO_V2))
waiting for download

But again, nothing I do from here seems to work. I did try to follow the instructions for forcing a fallback to previous firmware by tying P12 to the 3.3V output, but that does not appear to do anything (the red LED stays on solid red and I don't see any difference between trying it for 3, 6, or 9 seconds). Is there something I am missing? Thanks!

[robert-hh]

@helltoupee said in Trouble getting started on GPy:

waiting for download

In the state, where you see the above message, you have to close the Putty window and start the firmware updater.
It may also be that the data from the PC to the device does not arrive, and the typed characters are echoed because Putty is set to that mode.
Please note also that P0 and P1 are not the first two pins from the edge. The first Pin is Reset. That numbering is sometimes confusing for people who dealt a lot with DIL chip sockets.

[Elizar]

@helltoupee I tried an FTDI cable myself a few months ago with mixed success. I had a bunch of transmission errors during the upgrades. The transmission rates are a bit demanding for a simple mockup wiring.

Meanwhile I would always recommend to use the pycom expansion board for that purpose. It works like a charm, is not too expensive and I have flashed over a dozen boards without any problems since.

[helltoupee]

@robert-hh Thanks for the warning. I was able to confirm the echoing stopped if I removed either the Tx or Rx cable, so fortunately it does appear to be confirming the pycom is wired up correctly and receiving successfully.

[helltoupee]

@elizar I wouldn't have expected it since the Putty output looked fine, but it does appear to be issues related to poor signal quality. I took the breadboard out of the loop and attached the FTDI headers directly to the board headers with Molex cables and the flash finally took! Thanks for the suggestion!