Printable View
OK, I am going to make a better schematic image finally. Unfortunately I have detected a problem with Linux console - bidirectional communication is not reliable - characters are garbled so it's almost unusable. I am analyzing what's the problem because in PMON everything works fine. As I am using 16c450 chip without buffer, maybe that's the main reason....Quote:
Originally Posted by WlanMan
Can you use/set parity for your connection? That should eliminate the garbled characters...Quote:
Originally Posted by Technik
Is this supposed to work with wl500gx too?
I don't know much about these things, but why do we need that winbond IC? What's it doing? I saw serveral howtos for wrt54g, which only requires rs232 ic.
wl500gx should work in the same way as wrt54g, it does not need an external uart.
Aynone has a better schematics?
There are some things that I don't understand on this one... :(
OK, check the updated post here: http://wl500g.info/showpost.php?p=3312&postcount=3Quote:
Originally Posted by Alice
The bottom file should be a bit better. :)
Hi
I wonder how the Serial port is done on this Microsoft Box with Broadcom Chip. 4702 is the same as in wl500, but the board has only a 12pin connector labelt with rs232 which is not enough for a 8bit Bus interface...
Greets
Do you mean MN700 box mentioned in another thread? The 12 pin connector is JTAG and 10 pin connector labeled UART - that's the correct one. It is probably set of UART pins at TTL/CMOS levels. So any MAX232 compatible chip should be used to convert these levels to RS232. You need to explore the board to identify the connector pins assignment (or get a board schematics somewhere).Quote:
Originally Posted by WlanMan
that's a lot better, thanx!Quote:
Originally Posted by Technik
Now, question: I have an old board, from an XT i think.
the UART is a SiS 82C450 and near it it's a 18.432MHz XTAL. Do you think it will work as it should, with a 13 MHz XTAL?
Thanx!
I am afraid you HAVE TO use a 13 MHz XTAL (in ideal case it should be 12.75 MHz +/- 5%).Quote:
Originally Posted by Alice
yes, the xtal will be 12.75 mhz, no problem, but i think the uart is intended to work with a 18 mhz xtal. my question should be:
- if i have an uart that's intented to work with an 18 mhz xtal, will it work in this case if i use it with a 13 mhz xtal?
Find and check the data sheet for your specific chip then...Quote:
Originally Posted by Alice
The top frequency limit is important. I am sure the UART chip will work fine at any lower frequency.
i've searched for datasheet but I couldn't find it.
oh well... i'll try and see what it gets.
I presume that 1M means 1 uF capacitor, right?
I would just need 2 pins of the serial port to control a 240V relais.
Is this possible?
Read more and post here.
http://wl500g.info/showthread.php?p=11849#post11849
Which uart pinout does the bootloader use? TX0/RX0 or TX1/RX1Quote:
Originally Posted by Oleg
It's still a gx, but i can't measure voltage change, it's a constant 3.3v. If there was something data, its effective voltage should be less than that.
Unfortunately, i don't have a scope...
Does serial console enabled in your latest firmware?
Should be TX0/RX0. Yes, console is enabled.Quote:
Originally Posted by Josephus
For my understanding: is the UART now memory mapped? Or is it somewhere in PCI space?
Available in memory at base address 0xBF800000.Quote:
Originally Posted by dAF2000
How many people have actually installed an UART on their wl-500g? Are they working flawlessly? I'm thinking about adding one, but it would be nice to hear a few experiences first. (Yes I know it is easier to add a serial port with a pl2303, I have already done this but want to try something new...)
Technik: How did you know that a 12.75 MHz is the right rate? (Where in the source did you find it?)
I would like to use a PC16552D (dual UART); can the two UARTs share the interrupt? (INTR1 and INTR2 outputs OR'ed together and then connected to PIN17)
Some guy in the Dutch forum already has a serial port hooked up: http://wl500g.info/showthread.php?t=3587
Perhaps you can contact him...
Sorry for the late response... :rolleyes:Quote:
Originally Posted by wtzm
The original source was in some discussion about WRT54G. I expected that the same frequency could work in WL-500 as well --> true. If you use different XTAL, you will probably have to patch the serial driver - AFAIK there are Baud Rate Divisor constants.
Interrupt sharing should be OK. Please read this thread as well:
http://wl500g.info/showthread.php?t=1993