Go to advanced search

by grzegorzn
Sun Jul 14, 2013 8:23 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Short negative pule while opening UART
Replies: 8
Views: 2308

Re: Short negative pule while opening UART

The pl011 driver has piece of code with following comment in pl011_startup: /* * Provoke TX FIFO interrupt into asserting. */ I suppose we need patch similar to this one: https://lkml.org/lkml/2011/5/16/201 http://patches.linaro.org/1795/ Generating RTS is something I was thinking about too, but I h...
by grzegorzn
Sun Jul 14, 2013 5:57 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Short negative pule while opening UART
Replies: 8
Views: 2308

Re: Short negative pule while opening UART

The rule for data transmission is "be generous in what you accept, strict in what you produce". For sure my protocol should be error-tolerant and I can take care of that. But this satisfies only the first part of the rule. What about the second one? Maybe the glitch itself doesn't make Raspberry Pi ...
by grzegorzn
Sun Jul 14, 2013 2:08 pm
Forum: Troubleshooting
Topic: Board versions/revisions, or different assembly lines?
Replies: 67
Views: 19964

Re: Board versions/revisions, or different assembly lines?

My board:

Board ver.: BS1318
RAM Chip: Samsung 316 K4P4G324EB-AGC1 GKD0M4GFU
USB Chip: SMSC LAN9512-JZX B1315-A1B17 315271A CTI-TW
C6: 220 CFP 3B4
RG2: 17-33G RLC16
Issues: http://www.raspberrypi.org/phpBB3/viewt ... 7&p=387576
Distributor: Farnell
by grzegorzn
Sun Jul 14, 2013 1:34 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Short negative pule while opening UART
Replies: 8
Views: 2308

Re: Short negative pule while opening UART

I can find a workaround, but bug like this makes Raspberry Pi an unreliable, immature platform. That's sad.
If this is a known problem, where can I learn more about it? Is it a problem with Linux kernel or BCM2835?
by grzegorzn
Sat Jul 13, 2013 9:59 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Short negative pule while opening UART
Replies: 8
Views: 2308

Short negative pule while opening UART

Hello, I try to use serial port but I noticed strange behavior. When I open serial port, there is short negative pulse which lasts about 32 microseconds. This pulse is interpreted as a start bit by the other device which causes that garbage byte is received. I tried QSerialPort from Qt framework, na...

Go to advanced search