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fbergama / pigfx

PiGFX is a bare metal kernel for the Raspberry Pi that implements a basic ANSI terminal emulator with the additional support of some primitive graphics functions.
MIT License
278 stars 62 forks source link

unable to correctly set baudrate. #65

Closed willtco closed 3 years ago

willtco commented 3 years ago

I have followed the instructions to the letter, yet when booting the pi it indicates that the uart is expecting data at 115200 rather than the 9600buad set in pigfx.txt. I am using a pi-zero. It appears that pigfx is being ignored, I compiled the build as later I wish to modify the gfx.c file (but at the time of writing no changes have been made).

chregu82 commented 3 years ago

Please read this issue: https://github.com/fbergama/pigfx/issues/56

Does it even read the filesystem on the SD card?

willtco commented 3 years ago

Thanks for the reply, The pi boots up fine, at the bottom of the screen there's a message indicating the uart is waiting for 115200 8 n 1 - when I press a key on the keyboard a string of garbage appears, it seems clear that although 9600baud is set in the .txt file it only wants to play the 115200 baud rate. The issue you mention seems to be something quite different.

chregu82 commented 3 years ago

Please post a picture of your boot screen. I'm quite sure that PiGFX is unable to read the SD card and therefore cannot read the config file and therefore uses the default baudrate of 115200.

willtco commented 3 years ago

CIMG5316 This photo is of a compile of the downloaded uspi & piGFX zip files without any modification. afterlooking through the source I found the default is located in 'config.c' - when changing the default .uartBaudrate to 38400 my z80 card was able to send data to the pi and it was correctly represented on screen. However the usb keyboard was inoperative (except for the function keys which produced a few characters of garbage. My 2019 pigfix has many updates which I hope to transfer to the latest edition hence my need to compile from source - I thank you for your patience.

@willtco

chregu82 commented 3 years ago

It's like I thought. PiGFX is unable to read the SD card. You seem to have 4 partitions on your card. This doesn't work. Please delete all partitions, add a single new one, format it and put PiGFX on it. It should work afterwards.

willtco commented 3 years ago

part Yes I thought that but making a second card produced the same results, Using linux mint to examine the card shows only a single FAT partition, as below, the card was formatted under windows, it is a 2GB card as that's the smallest one I have. It contains only the few files for piGFX.

chregu82 commented 3 years ago

Could you use the windows tool for checking the partitions on the SD card? There seem to be more than your linux mint shows. If there's only one FAT formatted partition it should work fine.

willtco commented 3 years ago

pi

WIndows shows only a single partition as well - very confusing.

chregu82 commented 3 years ago

Does this SD card produce the boot screen you showed earlier?

willtco commented 3 years ago

yes same one.

willtco commented 3 years ago

Can you upload the MBR of a working card? - it should start with EB and end with 55 AA - I'll graft that onto a card, then format it - I think at some time the MBR - here is the MBR of the re-formatted 2gb card it clearly shows that Windows has replaced the true mbr with the first sector of a partition. If I can replace this with a good mbr from a 1GB card then reformat I believe that will cure the baudrate problem, but whether it will also cure the USB KBD I'm not sure Untitled

willtco commented 3 years ago

Update - after grafting a 500mb Fat 16 MBR onto the SD card, & re-formatting - the first part of the problem is solved - CIMG5317 Should I open the usb keyboard issue seperately?

chregu82 commented 3 years ago

I don't have a working MBR at the moment, that I could show you. Glad it's working now. Please open a new issue.

willtco commented 3 years ago

Thanks for your help.