A new Scrumpel is born

[Nick Brok]

Hi All,

Thanks to all tips read in this Forum I have designed a new Scrumpel computer (Scrumpel 7d). It has 1MB RAM, 32K ROM, 82c55 based I/O with hardware to connect a 4*20 LCD, 2 com ports, com1 with rts/cts. It has also 4 SPI ports which use the hardware SPI of the Z8S180. The config is almost the same as his successor (Scrumpel 7c). Below a photo of this board.

The LCD shows the status of the monitor and the current time. The external baudrate generator is removed, because I use the internal baudrategenerator of the Z8S180. Thanks Steve Cousins for showing me how to initialize the baudrate generator at 18.432 MHZ clock.

The PCB is in Eurocard format.

My RTC is running on interrupt in IM1 and uses the INT0 input. I have a question: Can I read from a register on which int input the interrupt came from? How is that register called?

Greetings,

Nick

[Steve Cousins]

Hi Nick,

That design has a great range of features. Very nice.

Are you going to put it in a case like your other systems?

Sorry, I don't have an answer to the interrupt question.

Steve

[Nick Brok]

Op donderdag 30 april 2020 09:21:22 UTC+2 schreef Steve Cousins:

Hi Nick,

That design has a great range of features. Very nice.

Are you going to put it in a case like your other systems?

I have found another case for it, complete from plastic. This one is still experimental... so building in a case is done when everything works as designed.

 

Sorry, I don't have an answer to the interrupt question.

You cannot know everything. ;-)

I hope someone else can answer my question?

Nick

[Wayne Warthen]

Nice system Nick.

 

My RTC is running on interrupt in IM1 and uses the INT0 input. I have a question: Can I read from a register on which int input the interrupt came from? How is that register called?

Under IM1, the only way to determine the source of the interrupt is to poll all devices that are connected to the interrupt line.  This requires that all devices have a way to indicate it has an interrupt pending.

Since this is a Z180-based system, why not use IM2?  Connect the RTC to either INT1 or INT2 and you will get a dedicated interrupt vector.

-Wayne

[Alan Cox]

Since this is a Z180-based system, why not use IM2?  Connect the RTC to either INT1 or INT2 and you will get a dedicated interrupt vector.

 As a note - you don't need to set IM2 on the IRQ0 line for this, you always get IM2ish behaviour (there's an extra IL register to configure) with the other lines. That can be useful if you need to have an interrupt line for non IM2 capable stuff and private vectors for a couple of other external devices.

Alan

[Nick Brok]

Hi Alan,

I don't understand you, I think.

IM2 uses the internal I and IL register to determine the vector address. You  can only use INT1 and INT2.

My RTC is hardwired to INT0. So I can use the I and IL register also in IM1?

I read the manual of the Z8S180 and understood that IM2 works for INT1 and INT2 with the I and IL register, INT0 reads the databus for its lowbyte vector.

So what do you mean, Alan?

Nick

Op donderdag 30 april 2020 20:02:58 UTC+2 schreef Alan Cox:

[Wayne Warthen]

On Thursday, April 30, 2020 at 11:28:45 AM UTC-7, Nick Brok wrote:

Hi Alan,

I don't understand you, I think.

IM2 uses the internal I and IL register to determine the vector address. You  can only use INT1 and INT2.

My RTC is hardwired to INT0. So I can use the I and IL register also in IM1?

I read the manual of the Z8S180 and understood that IM2 works for INT1 and INT2 with the I and IL register, INT0 reads the databus for its lowbyte vector.

So what do you mean, Alan?

I think Alan means that if you move the RTC over to either the INT1 or INT2 lines of the Z180, then you don't need to use IM2 (as I said) to get independent interrupt vectors.  Once you have an independent interrupt vector, then you will know which device set the interrupt.  So this only helps if you move the RTC interrupt line to INT1 or INT2.

-Wayne

[Nick Brok]

Hi,

For people who want to build Scrumpel 7d here is a link to hackaday: Scrumpel 7d on Hackaday

This can only build by experienced users.

Nick

[Nick Brok]

Hello,

Here a picture from Scrumpel 7d build in a nice plastic enclosure.

Greetings,

Nick

[Nick Brok]

My Scrumpel7d hackaday page is visited by a lot of people ( > 300 ). So my question is: did someone dare to build this Scrumpel?

The gerbers and all information are free available. For advanced users there must not any problem to build it.

The components are well available at MOUSER and RS-components. The modules except the DS3234 RTC at tinytronics. The RTC is available at spark-fun.

Greetings,

Nick

[Nick Brok]

The monitor for Scrumpel becomes more intelligent. It detects the RTC automatical, so if no RTC installed the RTC and RAM functions are disabled.

Here some screenshots:

Op vrijdag 12 juni 2020 om 16:27:42 UTC+2 schreef Nick Brok:

[Nick Brok]

Hello

Here the back-side from the Scrumpel7d enclosure:

Greetings,

Nick

[Nick Brok]

Here the newest enclosure for Scrumpel7d: 19 inch rack-mount.

Op zaterdag 25 juli 2020 om 13:29:51 UTC+2 schreef Nick Brok:

[Jim McGinnis]

Ahhh... So satisfying is that case!  Very fine.