I'm looking at the Atmel AT89C5115 20-pin 8051-based
microcontroller as part of a project I'm contemplating. The
instructions for the factory-default UART bootloader aren't entirely
clear on the subject.

According to the application note, the bootloader checks a
'hardware condition' to start the bootloader. Reading it, I'm
assuming that I have to tie pin1 of port1 low in order to start the
bootloader program.

Does anyone have any experience with this device...? I'd like to
know if I'm reading the information correctly. :-)

I don't have experience with particulary that part but I have with
T89C51CC01 and T89C51AC2 and thay all are ISP programmable
and they have the same bootloader so I don't think your uC should
be any different.

Those ISP uC can be put in ISP programming mode by software or
by hardware conditions.

By software is that you call api function to start bootloader or jump
to bootloader starting position I think it was something like F800hex.

By hardware was thet PSEN line had to be externaly pulled low
upon processor STARTUP.

There are also some other bits that affect the startup process, it
is the BLJB (Boot Loader Jump Bit), and it can be programmed
with Flip (Atmel's program for ISP programming).

But there are application notes on ISP programming and there is
also in uC datasheet a few pages on ISP programming, in CC01
and AC2 datasheets surely.

Best regards, Mickey

"Len Lekx" <LFLekx@NOSPAM.rogers.com> wrote in message
news:3fc03498.804334866@nntp...

On Sun, 23 Nov 2003 10:10:21 -0000, "Mickey" <mmmh@mmmmh.com> wrote:

The 89C5115 doesn't have a PSEN line - being a 20-pin device,
all memory access in internal.

I've read'em... but, unlike the 89C8252 and others, this one
doesn't have an 'example circuit with ISP capability' to draw on.

Len Lekx <LFLekx@NOSPAM.rogers.com> wrote:

configured to other Port-pins.
When the 'boot-mode' is reached successfully the processor answers a
send 'U' on the rs232 on every baudrate,
I have written a prg from exactly this purpose. Ive included every
feature, which can be invoked by ISP:
ftp://ftp.informatik.rwth-aachen.de/...r/projects/jMi
croISP1_0.inst.jar

Is it working now?

Greetings Klaus

Len Lekx wrote:

this is not a ATMEL device, rather XELTEK part, so anything could go
rw

On Sun, 23 Nov 2003 17:13:35 GMT, "Rein Wiehler"
<rwiehler@netscape.net> wrote:

Then how come I got the datasheet and bootloader info from the
Atmel website...? :-)

On Sun, 23 Nov 2003 17:25:01 +0100, Klaus.Kloos@kagi.com (Klaus Kloos)
wrote:

This I gathered... do I have to dedicate P1.0 (or whatever pin it
gets changed to...) as a bootloader-start signal? Or can I use it for
other purposes?

At the moment, I'm only gathering info for a *very* preliminary
idea... I may not melt solder on it for a while.

Thanks for the info, though...

Len Lekx wrote:

I did not see it under AT89 but found it under T89 when I looked again
sorry. rw

"Len Lekx" <LFLekx@NOSPAM.rogers.com> wrote in message
news:3fc1073d.858267799@nntp...
With care, you can use it - but one thing to watch, is if it is a general
IP, and the
device gets a WDOG fire when it is low, then the WDOG may not do what you
hope
- As a Status LED type output, it will be fine.

The device number/description seems a little skewed ?
Atmel _do_ have a T89C5115, but this is with 28/32 pin options.
This device should share bootloader info with the close sibling T89C51CC02,
and other same-release-time frame devices, like T89C51AD2, and T89C51RD2.

Part numbers AT89C5114/AT89C5116 do seem to relate to 20 pin devices,
but not (yet?) in general release.

Atmel is changing to AT89.. numbers, but care is needed, as
T89C51RD2 is NOTquite the same at the newer AT89C51RD2,
to replace the Atmel T89C51RD2 you need theAtmel AT89C51ED2

-jg

On Sun, 23 Nov 2003 19:20:13 GMT, "Rein Wiehler"
<rwiehler@netscape.net> wrote:

You think that's bad...? I've tried a parts-search on the
Digi-Key, Mouser and Allied sites, and NOT ONE of them have any
references for that particular chip. :-(

On Mon, 24 Nov 2003 09:23:25 +1300, "Jim Granville"
<no.spam@designtools.co.nz> wrote:

Might be easier to leave it dedicated to the bootloader signal.
What I have in mind won't require more than five or six pins, plus the
UART lines, anyway. :-)

That's part of what may be messing me up. I read the datasheet,
saw that the device was labelled T89C5115, and thought that it was a
typo.

And I messed up on the pin-count, too. I re-read the datasheet,
and see that it has options for 28, 24, and 32 pins.

No, but it is historical...
The T89.. numbers derive from the Temic Semi numbering ( which also used to
be TSC8.. and also TS8.. ) dating from before Atmel bought Temic.

Newest devices, designed by the Temic team, are being called
AT89C51ED2, AT89C51CC03 (etc) which brings the two families
into a consistant 'future terminology'.

The latest Atmel web info merges all the devices [TSC/TS/T/AT] into one
list, which can
look a bit of a mish-mash if you don't know how they got there...

It does mean searching for devices/web prices can get confusing

-jg

In article <OF8wb.9246$ws.826703@news02.tsnz.net>, Jim Granville
<no.spam@designtools.co.nz> writes
although it is closer.
--
Tim Mitchell