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In response to a couple people using the PICaxe cable I'll take some guesses as
to answers (one is on order and I'll try it out later this week).

The PICaxe cable uses the FTDI chip, but different IDs, however the Windows
registry may still list it as an FTDI device, which is where BASICtools looks
for compatible serial connections. Anyone want to answer whether that's true --
it means BASICtools would list that port in capital letters.

The PICaxe cable only brings out RXD and TXD, remember we name RXD and TXD from
the perspective of the BASICchip. I know at least one user has it up and
running.

How to stop a program-- PICaxe breaks the program on some character sequence
into the UART. In our case we look for a ctl-X or ESC character for 1 second
following a reset. If we do not see either of those then the user BASIC program
in started up.

While we could use a similar scheme to the PICaxe, we think it's better to do it
with reset. BASICtools allows for "Manual RESET" mode (renamed recently) which
will prompt the user to toggle the reset pin (you can connect up a pushbutton on
just use a wire).

Or you can add the serial stop feature to your BASIC program. If your program
runs forever, which most control programs will. Change the

WHILE 1
'.. do some stuff
LOOP

to

WHILE 1
'' do some stuff
if RXD(0)<>-1 then END
LOOP

will accomplish the serial break

PS: In response to a user comment, BASICtools has simplified its options menus,
removing some items normally not used in BASIC (but were used in C). So those
tools are out at setupBASIC.exe on the support page.

I assume you're talking about the AXE027 cable.

I does use the FTDI chip, but it is configured for inverted RXD/TXD relative to
a 'normal' chip.

It can be reconfigured using the FTDI utility software. Or use a couple of
inverters.

I would not use the AXE026 cable which connects the PC RS232 signals, could be
+/-12V, directly to the audio plug - and uses a couple of resistors to minimize
damage!

"basicnode" wrote:
>
> In response to a couple people using the PICaxe cable I'll take some guesses
as to answers (one is on order and I'll try it out later this week).
>
> The PICaxe cable uses the FTDI chip, .... BASICtools would list that port in
capital letters.

Yes, it does list in capitals.

> BASICtools allows for "Manual RESET" mode (renamed recently) which will prompt
the user to toggle the reset pin (you can connect up a pushbutton on just use a
wire).

Careful with 'just a wire' !!.

I was doing this, and had loads of trouble. I had a wire on /RES, and was
'dabbing' it to 0v, expecting the internal pullup to keep it high. The wire acts
as an aerial, and I got lots of spurious resets.

Cheers,

Buzby

I have not got one to test yet, but another user pointed out the signals for the
PICaxe are inverted. You can change that with FTDIs utilities, or probably
easier is to use a 7404

A push button to GND and pull up resistor on reset would best.

The idea --

WHILE 1
'' do some stuff
if RXD(0)<>-1 then END
LOOP

-- works a treat !

Just type a character into the box and the code stops !

I have an Axe027 and got it working by reconfiguring the I/0 polarity. However,
since it only brings out RX and TX it is somewhat limited. Besides I still need
to program Picaxe chips, and running the utility every time I change platforms
is a pain. Also as a long time Picaxe user, I have never really liked the stereo
plug setup. I cut it off and use header type connectors instead. Saves board
space.

So instead of AXE027 with the BasicChip on a breadboard, I have been using a
cheap CP2102 Based Adapter from EBAY that brings out all of the signals. This
adapter has "BAITE" marked on it and is the only one I have seen that brings out
all of the RS232 signals. It has worked flawlessly so far with a BasicChip on a
breadboard. About $3.00.

The AXE026 could possibly be used with a standard serial port, but external
clamping diodes would be needed on the TX line, (RX on the ARM) as well as a
current limit resistor. But again some functionality will be lost as it does not
bring out RTS ,et al.
I would avoid this though, as there are safer options.

Bill

I forgot to add..... The AXE027 TX out is fixed at 5V. I have not done much
research yet on the ARM pin tolerances, but if using this a 100 - 200 ohms
series resistor might be a good idea.

I have been studying the AXE027 cable and can send you lots of info on it for collaboration, such as a complete schematic, inside pictures of the PCB, details of its configuration under FTProg, etc. Can you contact me via a PM?

Tommy