MC68HC705C8

Hi,

Are there anyone here still using this chip. I googled for its programmer and the details for making one was deleted from the site due to no demand.

The chip was made by Motorola and second-sourced by ST Micro and we have plenty of them used in the line interface cards in an Ericsson AXE type exchange as well as in some Home Alarm systems.

Where can I get the programmer to read the contents of its eprom or is there an easy circuit I can construct to read the memory contents?

Is it possible to use its CPU core and connect external RAM and ROM like the 8051 does?

Thanks in advance.

Allen

Reply to
Allen Bong
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Allen,

We have original documentation for this tool at my office. The way I remember it there was a programmer published by Motorola for it.

Contact me off-line with what you documentation you need.

The part MC68HC705C8 does not have external address and data paths.

We do have software tools for the 6805 families.

Regards

Walter Banks Byte Craft Limited

519 888 6911

Allen B> Hi,

Reply to
Walter Banks

Allen,

We have original documentation for this part at my office. The way I remember it there was a programmer published by Motorola for it.

Contact me off-line with what you documentation you need.

The part MC68HC705C8 does not have external address and data paths.

We do have software tools for the 6805 families.

Regards

Walter Banks Byte Craft Limited

519 888 6911

Allen B> Hi,

Reply to
Walter Banks

Not really. There was a cheap emulator that used a very special port replacement chip. But how that worked was not published. There was a MC68HC705Cx variant with external bus as far as i remember. And there were MC68HC705E0 E1 chips that had no internal memory but external bus.

These are OTPs not FLASH: you can not reuse old chips.

MfG JRD

Reply to
Rafael Deliano

Allen,

Motorola sold and gave away thousands of EVM boards to emulate and debug 6805 code the 68HC05EVM board. this board could read and program MC68HC705C8 parts. There was so many of them there must be a few still around.

The MC68HC705C8 manuals have schematics for a programmer that uses a 2764 eprom as a project master. This programmer cannot read the MC68HC705C8 parts.

One check you should make is that you have MC68HC705C8 and not the later MC68HC705C8A parts. They are close but not the same.

Regards

-- Walter Banks Byte Craft Limited

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Reply to
Walter Banks

I have never seen any of those EVM boards. Do you have one that you dont need any more? What's the software that came with the board? Are the software DOS based or windows based?

From the 68hc705c8a datasheet as indicated by Rafael, the programmer in section 9 of the pdf mentioned that it is possible to read the PROM contents by setting switches S3 through S6 to "off on on off" and the content is sent through the serial interface to a PC at 4800 b/s. I am going to construct this board and see if it works. I hope the security bit is not set so I am keeping my fingers crossed. Though I have never program in 6805 before but I have used 6803 and I think their instruction sets should be quite close.

I have all 3 packagings of the chip namely PDIP, PLCC and QFP and I remember that some of the PDIP were made by Toshiba in the 90s.

Thanks very much for your reply!

Allen

Reply to
Allen Bong

Oops, that's my worse nightmare. But anyway I am going to construct the programmer. Thanks for the datasheet too! It is very informative.

May be I should start with a 68HC705E0 or E1 chips. The EPROM version with the glass window ones must be very, very expansive. Not for hobbyist I'm afraid.

Is this 68HC908 recommended for hobbyist or am I better off with

68HC11 which is more popular? There are flash and eeprom version of 68HC11 too, isn't it?

Allen

Reply to
Allen Bong

One check you should make is that you have MC68HC705C8 and not

BTW do you know the difference of these 2 chips? It was not mentioned in the datasheet of the HC705C8A.

Allen

Reply to
Allen Bong

I used to be a HC08 hobbyist and when I outgrew them, I went the AVR route.

It's not a move that I have regretted and the only thing that I very occasionally miss is the lack of a USB device in PDIP - ie: there's no AVR equivalent of the HC08's JB8.

OTOH, you can get FTDI chips packaged on a PDIP circuit board for not much money (at least here in the UK) and at the moment, where I would have used a JB8 before, I currently use either the AVR's hardware UART or a software (Tx only) UART running on it's own timer and I'm not really bothering with the FTDI chips (at the moment).

Simon.

--
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980's technology to a 21st century world
Reply to
Simon Clubley

There is not much support now for getting OTPs, windowed/erasable ICs. If you do not have to support legacy industrial products stay clear of HC05/HC11.

Correct name is MC68HC05E0, C0 as they have no (program-)memory on chip. They seem to exist:

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But getting them in small quantity may prove hard. I have used the E0 in FN-package ( thats PLCC68 ) and 32k SRAM and 32kEPROM with a FORTH i have written for it to develop software more comfortably then with the emulator. While i can dig out this old stuff, as said: if you do not have to support legacy industrial products ...

MfG JRD

Reply to
Rafael Deliano

MfG JRD

Reply to
Rafael Deliano

That's bad wording on my part. Before anyone spends time looking for a FTDI chip packaged in a PDIP case, I meant that you could get normal FTDI chips mounted on a circuit board with 0.1 inch pitch pinouts.

Simon.

--
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980's technology to a 21st century world
Reply to
Simon Clubley

The newer MC9S08' series of chips are a much improved version of the older 8-bit products. In fact, some can do the job of the older

68HC11's. It isn't necessary to program in assembler. I've written several engine control support programs for off-road vehicles in 'C' on various flavors of the newer 8-bit products. 'C' running with a small OS is very common on these devices.

Frank

Reply to
Cmplx80

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