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N8 (N8VEM) 4617 [message #6271] Sun, 28 April 2019 06:40 Go to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
Hi everybody,

because i grew up with MSX and C64 and so on, I decided to build the N8 and ordered the PCB for it.
But i can't get it to work.
I ordered a few parts from Ali Express and first I thought that that was the problem.
But when a got in the parts from Mouser and replaced the parts from Ali with the parts from mouser it stil didn't work.

I measured 5V on all the IC's (5,1 to be exactly) so the power supply works fine.
I Checked if i made a mistake by misplacing an IC on the wrong place, but as far as i can see I didn't.

I only have an Multimeter and an simple logic analyzer( USB Logic Analyzer 24M 8CH Microcontroller ARM FPGA Debug Tool)(put in google to see)
and an (very) simple Oscilloscope DSO138 (Analog bandwidth : 0 - 200KHz)
So I don't have real tools sorry.

I used the BOM from "retrobrewcomputers.org/doku.php?id=boards:sbc:n8:n8"
but my board is a little different then a lot of photo's that i see at the builder pages:
" retrobrewcomputers.org/n8vem-pbwiki-archive/0/35845334/48860 639/31624471/42471911/index.htm "
I also have more jumpers.

I have tried only one Bios: " retrobrewcomputers.org/doku.php?id=software:firmwareos:romwb w:start "
N8_std.rom
Because romwbw is the common bios and should work on any board.
I programmed the bios with an Eprom Programmer (i used an EEprom and a normal one(the one you have to erase with UV)Wink.

I used Serial (RS232) and Composiet out.
Both of them don't work.
the serial I connected directly to the Com port 1 of my PC.
and when that did not work 1 used an USB-->serial adapter.
but stil no connection.
I used Putty and ZOC7 terminal.

Are there any measure points or tests I can do, to see which part of the print is oké?.

because I could not find the Germanium Diodes (D2,D3,D4,D5 Germanium or Schottky (1N270 or 1N5280)Wink I replaced them for 1N4148.

Is there someone who can help me?

I will upload some foto's of my board.

Thank you in advance.

Greeting Matthijs.


Re: N8 (N8VEM) 4617 [message #6272 is a reply to message #6271] Sun, 28 April 2019 06:51 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
/forum/index.php?t=getfile&id=1341&private=0Photo
Re: N8 (N8VEM) 4617 [message #6273 is a reply to message #6272] Sun, 28 April 2019 06:56 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
/forum/index.php?t=getfile&id=1342&private=0other Z8S180 processor
Re: N8 (N8VEM) 4617 [message #6277 is a reply to message #6271] Sun, 28 April 2019 12:18 Go to previous messageGo to next message
wtim55 is currently offline  wtim55
Messages: 13
Registered: September 2018
Location: Sao Paulo SP, BR
Junior Member
278/5000
Hello, jojoenco,
This is my N8 system. I have only used the serial port.
My configuration files for rom file compilation are as follows. They are the most current version of ROMWBW available at https://github.com/wwarthen/RomWBW. (Romwbw 2.9.1 pre 12)

N8_std.asm

;
;=========================================================== =======================================
; N8 STANDARD CONFIGURATION
;=========================================================== =======================================
;
#include "cfg_n8.asm"
;
Z180_CLKDIV .SET 1 ; 0=OSC/2, 1=OSC, 2=OSC*2
Z180_MEMWAIT .SET 1 ; MEMORY WAIT STATES TO INSERT (0-3)
Z180_IOWAIT .SET 3 ; IO WAIT STATES TO INSERT (0-3)
;
SDMODE .SET SDMODE_CSIO ; FOR N8 PROTOTYPE (DATECODE 2511), USE SDMODE_N8
;
CRTACT .SET FALSE ; TRUE TO ACTIVATE CRT AT STARTUP (BOOT ON CRT)



cfg_n8.asm

;
;=========================================================== =======================================
; ROMWBW 2.X CONFIGURATION FOR N8
;=========================================================== =======================================
;
; BUILD CONFIGURATION OPTIONS
;
CPUOSC .EQU 18432000 ; CPU OSC FREQ
RAMSIZE .EQU 1024 ; SIZE OF RAM IN KB, MUST MATCH YOUR HARDWARE!!!
DEFSERCFG .EQU SER_38400_8N1 ; DEFAULT SERIAL LINE CONFIG (SHOULD MATCH ABOVE)
INTMODE .EQU 2 ; 0=NONE, 1=INT MODE 1, 2=INT MODE 2
;
CRTACT .EQU FALSE ; CRT ACTIVATION AT STARTUP
VDAEMU .EQU EMUTYP_ANSI ; DEFAULT VDA EMULATION (EMUTYP_TTY, EMUTYP_ANSI, ...Wink
;
DSKYENABLE .EQU FALSE ; TRUE FOR DSKY SUPPORT (DO NOT COMBINE WITH PPIDE)
;
HTIMENABLE .EQU FALSE ; TRUE FOR SIMH TIMER SUPPORT
SIMRTCENABLE .EQU FALSE ; SIMH CLOCK DRIVER
DSRTCENABLE .EQU TRUE ; DS-1302 CLOCK DRIVER
DSRTCMODE .EQU DSRTCMODE_STD ; DSRTCMODE_STD, DSRTCMODE_MFPIC
DSRTCCHG .EQU TRUE ; DS-1302 CONFIGURE CHARGE ON (TRUE) OR OFF (FALSE)
;
ASCIENABLE .EQU TRUE ; TRUE FOR Z180 ASCI SUPPORT
UARTENABLE .EQU FALSE ; TRUE FOR UART SUPPORT (ALMOST ALWAYS WANT THIS TO BE TRUE)
UARTOSC .EQU 1843200 ; UART OSC FREQUENCY
SIOENABLE .EQU FALSE ; TRUE FOR ZILOG SIO/2 SUPPORT
SIOMODE .EQU SIOMODE_RC ; SIOMODE_RC, SIOMODE_SMB
ACIAENABLE .EQU FALSE ; TRUE FOR MOTOROLA 6850 ACIA SUPPORT
;
VDUENABLE .EQU FALSE ; TRUE FOR VDU BOARD SUPPORT
CVDUENABLE .EQU FALSE ; TRUE FOR CVDU BOARD SUPPORT
NECENABLE .EQU FALSE ; TRUE FOR uPD7220 BOARD SUPPORT
TMSENABLE .EQU TRUE ; TRUE FOR N8 (TMS9918) VIDEO/KBD SUPPORT
VGAENABLE .EQU FALSE ; TRUE FOR VGA VIDEO/KBD SUPPORT
;
SPKENABLE .EQU FALSE ; TRUE FOR RTC LATCH IOBIT SOUND
AYENABLE .EQU TRUE ; TRUE FOR AY PSG SOUND
;
MDENABLE .EQU TRUE ; TRUE FOR ROM/RAM DISK SUPPORT (ALMOST ALWAYS WANT THIS ENABLED)
MDTRACE .EQU 1 ; 0=SILENT, 1=ERRORS, 2=EVERYTHING (ONLY RELEVANT IF MDENABLE = TRUE)
;
FDENABLE .EQU TRUE ; TRUE FOR FLOPPY SUPPORT
FDMODE .EQU FDMODE_N8 ; FDMODE_DIO, FDMODE_ZETA, FDMODE_DIDE, FDMODE_N8, FDMODE_DIO3
FDTRACE .EQU 1 ; 0=SILENT, 1=FATAL ERRORS, 2=ALL ERRORS, 3=EVERYTHING (ONLY RELEVANT IF FDENABLE = TRUE)
FDMEDIA .EQU FDM144 ; FDM720, FDM144, FDM360, FDM120 (ONLY RELEVANT IF FDENABLE = TRUE)
FDMEDIAALT .EQU FDM720 ; ALTERNATE MEDIA TO TRY, SAME CHOICES AS ABOVE (ONLY RELEVANT IF FDMAUTO = TRUE)
FDMAUTO .EQU TRUE ; SELECT BETWEEN MEDIA OPTS ABOVE AUTOMATICALLY
;
RFENABLE .EQU FALSE ; TRUE FOR RAM FLOPPY SUPPORT
RFCNT .EQU 1 ; NUMBER OF RAM FLOPPY UNITS
;
IDEENABLE .EQU FALSE ; TRUE FOR IDE SUPPORT
IDEMODE .EQU IDEMODE_DIO ; IDEMODE_DIO, IDEMODE_DIDE
IDECNT .EQU 1 ; NUMBER OF IDE UNITS
IDETRACE .EQU 1 ; 0=SILENT, 1=ERRORS, 2=EVERYTHING (ONLY RELEVANT IF IDEENABLE = TRUE)
IDE8BIT .EQU FALSE ; USE IDE 8BIT TRANSFERS (PROBABLY ONLY WORKS FOR CF CARDS!Wink
;
PPIDEENABLE .EQU TRUE ; TRUE FOR PPIDE SUPPORT (DO NOT COMBINE WITH DSKYENABLE)
PPIDEMODE .EQU PPIDEMODE_N8 ; PPIDEMODE_SBC, PPPIDEMODE_DIO3, PPIDEMODE_MFP, PPIDEMODE_N8, PPIDEMODE_RC
PPIDETRACE .EQU 1 ; 0=SILENT, 1=ERRORS, 2=EVERYTHING (ONLY RELEVANT IF PPIDEENABLE = TRUE)
PPIDE8BIT .EQU FALSE ; USE IDE 8BIT TRANSFERS (PROBABLY ONLY WORKS FOR CF CARDS!Wink
;
SDENABLE .EQU TRUE ; TRUE FOR SD SUPPORT
;SDMODE .EQU SMDODE_N8 ;
SDMODE .EQU SDMODE_CSIO ; SDMODE_JUHA, SDMODE_CSIO, SDMODE_UART, SDMODE_PPI, SDMODE_DSD
SDTRACE .EQU 1 ; 0=SILENT, 1=ERRORS, 2=EVERYTHING (ONLY RELEVANT IF IDEENABLE = TRUE)
SDCSIOFAST .EQU FALSE ; TABLE-DRIVEN BIT INVERTER
;
PRPENABLE .EQU FALSE ; TRUE FOR PROPIO SUPPORT
PRPSDENABLE .EQU FALSE ; TRUE FOR PROPIO SD SUPPORT
PRPSDTRACE .EQU 1 ; 0=SILENT, 1=ERRORS, 2=EVERYTHING (ONLY RELEVANT IF PRPSDENABLE = TRUE)
PRPCONENABLE .EQU FALSE ; TRUE FOR PROPIO CONSOLE SUPPORT (PS/2 KBD & VGA VIDEO)
;
PPPENABLE .EQU FALSE ; TRUE FOR PARPORTPROP SUPPORT
PPPSDENABLE .EQU FALSE ; TRUE FOR PARPORTPROP SD SUPPORT
PPPSDTRACE .EQU 1 ; 0=SILENT, 1=ERRORS, 2=EVERYTHING (ONLY RELEVANT IF PPPENABLE = TRUE)
PPPCONENABLE .EQU FALSE ; TRUE FOR PROPIO CONSOLE SUPPORT (PS/2 KBD & VGA VIDEO)
;
HDSKENABLE .EQU FALSE ; TRUE FOR SIMH HDSK SUPPORT
;
PPKTRACE .EQU 1 ; 0=SILENT, 1=ERRORS, 2=EVERYTHING (ONLY RELEVANT IF PPKENABLE = TRUE)
KBDTRACE .EQU 1 ; 0=SILENT, 1=ERRORS, 2=EVERYTHING (ONLY RELEVANT IF KBDENABLE = TRUE)
;
TERMENABLE .EQU FALSE ; TERM PSEUDO DEVICE, WILL BE ENABLED IF A VDA IS ENABLED
ANSITRACE .EQU 1 ; 0=SILENT, 1=ERRORS, 2=EVERYTHING (ONLY RELEVANT IF ANSIENABLE = TRUE)
;
BOOTTYPE .EQU BT_MENU ; BT_MENU (WAIT FOR KEYPRESS), BT_AUTO (BOOT_DEFAULT AFTER BOOT_TIMEOUT SECS)
BOOT_TIMEOUT .EQU 20 ; APPROX TIMEOUT IN SECONDS FOR AUTOBOOT, 0 FOR IMMEDIATE
BOOT_DEFAULT .EQU 'Z' ; SELECTION TO INVOKE AT TIMEOUT
;
Z180_CLKDIV .EQU 1 ; 0=OSC/2, 1=OSC, 2=OSC*2
Z180_MEMWAIT .EQU 1 ; MEMORY WAIT STATES TO INSERT (0-3)
Z180_IOWAIT .EQU 3 ; IO WAIT STATES TO INSERT (0-3)
;
PIO_4P .EQU FALSE ; TRUE FOR ECB-4PIO PIO SUPPORT
PIO_ZP .EQU FALSE ; TRUE FOR ECB-ZILOG PERIPHERALS BOARD
PPI_SBC .EQU FALSE ; TRUE FOR SBC V2 8255 (IF NOT BEING USED FOR PPIDE)


I made some changes to the cfg_n8.asm file until I succeeded.

Hope this helps

Jorge
Re: N8 (N8VEM) 4617 [message #6278 is a reply to message #6277] Sun, 28 April 2019 12:59 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
Hi Jorge,

Thank you for the fast reply and thank you for your Rom file.
I am gonna try that tomorrow and let you now how that works out.

I see your MAX232 is missing do you use an external RS232 Converter to USB or do connect it different to something else?
or should it work the way i have it connected now:
https://retrobrewcomputers.org/n8vem-pbwiki-archive/0/358453 34/48860639/31624471/42471911/44100670/hc-serial%20cable.JPG
followed the above connections.

Greeting Matthijs.


Re: N8 (N8VEM) 4617 [message #6279 is a reply to message #6278] Sun, 28 April 2019 13:32 Go to previous messageGo to next message
wtim55 is currently offline  wtim55
Messages: 13
Registered: September 2018
Location: Sao Paulo SP, BR
Junior Member
I'm not using MAX232
I use a rs232 / USB converter cable purchased on Ebay.
These cables have only the Tx and Rx signals.
The CTS and RTS signals on pins 11 and 12 of the MAX232 socket are jumped.
The terminal emulator I'm using is the TeraTerm.

/forum/index.php?t=getfile&id=1346&private=0


/forum/index.php?t=getfile&id=1347&private=0
Re: N8 (N8VEM) 4617 [message #6281 is a reply to message #6279] Mon, 29 April 2019 13:55 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
/forum/index.php?t=getfile&id=1348&private=0Still no luck.

Reprogrammed the Eprom with your Rom.
And tried it with the Max232.
And that didn't work.

Then I took out the Max232 and used the USB -->RS232 converter.
and connected the 3 connections on the socket(where the Max232 was before) with 3 wires. (long ones in a hurry)
Just to test but only rubbish when i turn off the power supply.
Nothing for the rest.
pressed the reset button but stil no response.

used TeraTerm instead off Putty and zoc7 just to be sure.


/forum/index.php?t=getfile&id=1348&private=0
Re: N8 (N8VEM) 4617 [message #6282 is a reply to message #6281] Mon, 29 April 2019 14:02 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
/forum/index.php?t=getfile&id=1349&private=0

Oops double Photo.
this should be the one

I wil try some more options tomorrow.

Smile
Re: N8 (N8VEM) 4617 [message #6293 is a reply to message #6282] Mon, 13 May 2019 13:45 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
a little update.

I tried a lot of rom's but no succes with the serial port's.
then i thought lets try the MSX Cbios :
https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=b oards:sbc:n8:n8-ddw-msxbios_9_9_2017.zip

then sometimes when i turn the power on i get Sprites on my screen.
And sometimes i get: ERROR: CALLED NON EXISTING BASIC.
See pictures.
So that means the system does something but no serial with CP/M.(I think that CP/M doesn't even boot)

and it is strange that sometimes i get sprites and sometime's text.

i am out of options for the moment.

I have the board for the Harlequin (ZX spectrum) and some of the parts for it came in, so i am gonna start on that project until i get a bright idea for the N8.

Or maybe someone else can put me in the right direction.

Jorge helped me a lot by telling me that it is probably the firmware (Bios) that is wy i tried a lot of firmware's and found out that the MSX Cbios gives output to my black and white mini television.

but i am not that good in building the rom's myself.
Perhaps that is the big problem.

Greeting Matthijs
Re: N8 (N8VEM) 4617 [message #6295 is a reply to message #6293] Mon, 13 May 2019 22:30 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
See if you can redirect output from serial to video console.

I think you need to ...

Change the CRTACT setting in ROMWBW to TRUE.
Jumper k20 2-3
And change the following code HBIOS code to remove the (PLATFORM != PLT_N8) &

#IF CRTACT
;
; BIOS IS CONFIGURED TO AUTO ACTIVATE CRT DEVICE.  FIRST,
; CHECK TO SEE IF WE HAVE A VALID CRT DEVICE TO USE.
;
	LD	A,(CB_CRTDEV)		; GET THE CRT DEVICE
	INC	A			; INCREMENT TO TEST FOR $FF
	JR	Z,INITSYS3		; IF NO CRT DEVICE, BYPASS CONSOLE SWITCH
;
; IF PLATFORM HAS A CONFIG JUMPER, CHECK TO SEE IF IT IS JUMPERED.
; IF SO, BYPASS SWITCH TO CRT CONSOLE (FAILSAFE MODE)
;
#IF ((PLATFORM != PLT_N8) & (PLATFORM != PLT_MK4) & (PLATFORM != PLT_RC) & (PLATFORM != PLT_RC180) & (PLATFORM != PLT_EZZ80))
	IN	A,(RTC)			; RTC PORT, BIT 6 HAS STATE OF CONFIG JUMPER
	BIT	6,A			; BIT 6 HAS CONFIG JUMPER STATE
	JR	Z,INITSYS3		; Z=SHORTED, BYPASS CONSOLE SWITCH
#ENDIF

No warranty lol Smile

Regards Phil
Re: N8 (N8VEM) 4617 [message #6297 is a reply to message #6295] Wed, 15 May 2019 01:47 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Hi jojenco,

Been thinking about your problem ...

I don't have an N8 but maybe be able to help ...

If your machine is not giving a HALT signal then there is a good chance your board is running but not communicating.

We could insert halt instructions in the code to find out how far in the boot process it is getting.

Are you able to edit and build new N8 ROMs? If not I can assist.

Best Wishes Phil
Re: N8 (N8VEM) 4617 [message #6305 is a reply to message #6297] Thu, 16 May 2019 14:12 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
Hi Phil,

Thank you for your info about the Rom.
I was able to : Change the CRTACT setting in ROMWBW to TRUE
And remove the : PLATFORM != PLT_N8

And i got this. see photo.(IMG_20190515_230335.jpg)
And this is more than i expected.
I thought like the many Roms i tried that nothing would happen.
But this looks like something is starting but then stops.

So i will be more than happy if you can help me.

Sometimes it takes a day or maybe 2 days for me to try it out and answer on the forum.
Because i am out to work from 8:00 until i get home at 20:30 (including travel time).
So i don't have a lot of time during the week.
most of the tests i normally do at the weekend.

It is also possible that this model board(4617) is different (newer) then al the other models i have seen.
And i used the BOM(build of material) from the older boards (could not find a newer one)but some parts where different.
So i hope that that is not the problem.

i can edit and build ROM's but only if someone tells me where i have to change things, like you did in the last mail.

Thank you.

Greeting Matthijs.

Re: N8 (N8VEM) 4617 [message #6306 is a reply to message #6305] Fri, 17 May 2019 02:00 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Terrific, I'll have a look at the code and see if we can get some output to the screen to see how far the boot process is getting.

Also try removing j20 2-3 and see if you get different result - i think I misinterpreted the setting.

Get back to you soon.

regards Phil.

Re: N8 (N8VEM) 4617 [message #6307 is a reply to message #6306] Fri, 17 May 2019 02:45 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Ok, after looking at the code, the TMS9918 is not considered one of the console devices at bootup so it is not preinitialized for display of the boot message - so we are not going to see any output to this device, so you can probably revert thos previous changes.

Looking at the tms code in relation to your display output I'm pretty sure that the screen is being initialized - so lets confirm that:

So in tms.asm do this change:

TMS_VDARES:
	LD	DE,0			; ROW = 0, COL = 0
	CALL	TMS_XY			; SEND CURSOR TO TOP LEFT
	LD	A,' '			; BLANK THE SCREEN              <<<<<<<<<<< change to LD A,'*'
	LD	DE,TMS_ROWS * TMS_COLS	; FILL ENTIRE BUFFER
	CALL	TMS_FILL		; DO IT
	LD	DE,0			; ROW = 0, COL = 0
	CALL	TMS_XY			; SEND CURSOR TO TOP LEFT
	XOR	A
	DEC	A
	LD	(TMS_CURSAV),A
	CALL	TMS_SETCUR		; SET CURSOR
	
	XOR	A			; SIGNAL SUCCESS
	RET

This should fill the screen with stars if it getting to the TMS 9918 initialization code.

The TMS code is also after the serial intialization code, so we will be able to tell if the serial ports are initialized as well.

Regards Phil
Re: N8 (N8VEM) 4617 [message #6308 is a reply to message #6307] Fri, 17 May 2019 03:45 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
I have tested this on my SBC...

If I do not plug in my CPU board then there is no display out of the TMS 9918 - the tv does not recognize a signal.
If I disable the TMS driver then the tv displays a blank screen but no cursor - the tv appears to recognize a signal but does not display anything.
If I enable the TMS driver the I get a blank screen with a cursor like yours.
If I do the change described above, I get a screen full of stars.

So cursor is definately coming from initialization.

Let me know if you seeing stars.

Regards Phil
Re: N8 (N8VEM) 4617 [message #6309 is a reply to message #6308] Sat, 18 May 2019 07:38 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
Yes!
how happy one can be with a screen full of stars.

Jumper 20 (K20) changes nothing.
so i leave it on 2-3

Greeting Matthijs.
Re: N8 (N8VEM) 4617 [message #6311 is a reply to message #6309] Sat, 18 May 2019 10:06 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Fantastic.

So it looks like your machine is booting ok. Have you connected your DSO138 to the serial Tx and Rx lines to see if there is any activity? Check you can see Tx activity from your computer usb/serial adapter first without being connected to N8 - with flow control set to none. Once you can see output try and see if you can see anything coming from the N8 after resetting the machine.

I will have a look at the serial and tms code and see if we can get some output to the video screen to see what is going.

Regards Phil

[Updated on: Sat, 18 May 2019 10:07]

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Re: N8 (N8VEM) 4617 [message #6312 is a reply to message #6311] Sat, 18 May 2019 11:20 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
I think that indeed the machine is booting but stops half way.
I have connected the TX and RX lines from the serial port to the DSO0138 just now and when I type something then I get a response.
but when I connect the same connections to the board then I get nothing and the scope gets out of range in RED colour.

Re: N8 (N8VEM) 4617 [message #6313 is a reply to message #6312] Sat, 18 May 2019 11:23 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
From the Serial port
Re: N8 (N8VEM) 4617 [message #6314 is a reply to message #6313] Sat, 18 May 2019 11:24 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
from N8
Re: N8 (N8VEM) 4617 [message #6315 is a reply to message #6314] Sat, 18 May 2019 11:46 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Hi Matthijs,

Please try adding this code to hbios.asm

INITSYS3:
;
	LD	A,(CB_CRTDEV)		; GET CRT DISPLAY DEVICE                ***** add this line
	LD	(CB_CONDEV),A		; SAVE IT AS ACTIVE CONSOLE DEVICE      ***** and this line
	CALL	PRTSUM			; PRINT UNIT/DEVICE SUMMARY TABLE
;
; CHAIN TO OS LOADER

This should display the device summary and the boot loader selection.

If this works then we can now output stuff to the screen for debugging.

Its 3am, I'm off to bed, will check back in the morning and take a look at your serial pictures.

Regards Phil.
Re: N8 (N8VEM) 4617 [message #6316 is a reply to message #6315] Sat, 18 May 2019 13:29 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
Oops 3am, sorry didn't now. here it is 22:24 at this moment.

But very good news.
It works, YesYesYes finally.

Re: N8 (N8VEM) 4617 [message #6317 is a reply to message #6316] Sat, 18 May 2019 13:33 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
CP/M
Re: N8 (N8VEM) 4617 [message #6318 is a reply to message #6317] Sat, 18 May 2019 20:32 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Good Morning, that's great news.

Here's a couple things to try:

Try booting without the DS1302 installed.

With the DS1302 installed try and set the real time clock using RTC.COM and confirm it is working. info here:

https://www.retrobrewcomputers.org/doku.php?id=software:firm wareos:romwbw:apps#rtc_command

Also,

Please try the Mode command and see if changing any of the serial settings helps.

https://www.retrobrewcomputers.org/doku.php?id=software:firm wareos:romwbw:apps#mode_command

I will set up my Mark IV and SCG card and get back to you.

With your serial pictures - red is indication negative voltage, so either your connections were reverse or there is a big problem. Hopefully the former.
Can you please tell me output of STAT DEV: and STAT VAL: is?

Regards Phil



[Updated on: Sat, 18 May 2019 20:46]

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Re: N8 (N8VEM) 4617 [message #6320 is a reply to message #6318] Sun, 19 May 2019 01:34 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
Good morning,

Yes really great.

I played a little last night with basic and CP/M.
And tried the Floppy and the SD-CARD reader.
I can format the floppy and the SD-card also but when I read from it I get rubbish.
(just for you to know)

I tried booting without the DS1302 but then no response, just a black screen.
I chanced the realtime clock with RTC.COM and it is half working(not the right date), DS1302 back in again of course. (RTC.jpg)

I chanced the serial Baud rate, changing to 9600 went fine but no response on the serial port.(Serial1.jpg Serial2.jpg)


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Re: N8 (N8VEM) 4617 [message #6321 is a reply to message #6320] Sun, 19 May 2019 01:50 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
and the rest:

Can you please tell me output of STAT DEV: and STAT VAL: is? (STAT.jpg)

Now that it works I changed the monitor to a bigger one with color.

Greeting Matthijs.
  • Attachment: STAT.jpg
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Re: N8 (N8VEM) 4617 [message #6322 is a reply to message #6321] Sun, 19 May 2019 03:18 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
CP/M has some very basic redirection capability.

STAT DEV tells us what the current redirection assignment is, STAT VAL tells us the options.

The primiary I/O device is CON: and it is normally assigned with TTY: i.e. CONsole I/O is through the TTY device which in normally the primary serial port.

Our code trick has change CON: to CRT: which is the video output/PS2 keyboard option.

CP/M supports a printer device - LST: The list device is assigned with TTY: also so anything "LIST"ed will go to the primary serial port i.e. LIST filename.txt

To assist debugging we want to see if we can get any output on the serial line. If you press Ctrl-P everything that goes to the CON: device will also be echoed to the LST: device.

So try that and see if you can see any output on the TX line.

You should be able to type STAT CON:=TTY: and the N8 will then redirect all I/O through the serial interface again.

Where abouts did you get your board from? Do you have any schematics or circuits for this version (excluding what is on the wiki). I have messaged Andrew but no response yet.

I'm interested in seeing what speed your system thinks it is running so will look at what info we can get.

Regards Phil.

Re: N8 (N8VEM) 4617 [message #6323 is a reply to message #6322] Sun, 19 May 2019 04:22 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
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Hi Matthijs,

Can you please check your RTC again. When setting time number should be two digits i.e. month 5 = 05

Correct running clock is critical for correct speed and serial setup.

Please confirm correct time and date can be set and it keeps time correctly.

Also try setting in std_n8.asm:

DSRTCENABLE .SET FALSE ; DS-1302 CLOCK DRIVER

I think if no RTC is installed it will use the default speed rather than trying to measure it.

Also have you tried connect CTS to ground rather than RTS?

Regards Phil.
Re: N8 (N8VEM) 4617 [message #6324 is a reply to message #6322] Sun, 19 May 2019 04:49 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
I got the board from Tod:

"N8 Home Computer (ECB HC3v2) 20 $20 Todd Goodman"
https://www.retrobrewcomputers.org/doku.php?id=boardinventor y

And the board is High Quality.
But I didn't find more information about this board.
so I just used the Wiki.
found no new Schematics or circuits.

I have to go out for 2 Hours so I will do the rest later.

Greeting Matthijs.

Re: N8 (N8VEM) 4617 [message #6325 is a reply to message #6324] Sun, 19 May 2019 05:00 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
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Cool, I will contact Todd and see if he can share the files so we can see schematics.

Regards Phil.
Re: N8 (N8VEM) 4617 [message #6326 is a reply to message #6325] Sun, 19 May 2019 07:31 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
The time can be set correctly I did't press (S)ET.
So it wasn't stored.

Now I got This(Time1.jpg) even after Reset button I get(Time2.jpg).

also I have R47 which doesn't exist in the BOM (and the Circuit) but because it is in the Floppy controller circuit and I thought I figure it out later I left out any resistor there.(R47.jpg took out the oscillator)
So I did't think it was important but that could be why I got rubbish from the floppy.

Do you mean the cfg_N8.asm ?
Because N8_std.asm has no "DSRTCENABLE .SET FALSE ; DS-1302 CLOCK DRIVER"
but in the file it says include cfg_N8.asm

Greeting Matthijs
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Re: N8 (N8VEM) 4617 [message #6327 is a reply to message #6326] Sun, 19 May 2019 07:45 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
whatever I Try with the Serial port still no signal.
Also CTS to the ground makes no difference.
Re: N8 (N8VEM) 4617 [message #6328 is a reply to message #6327] Sun, 19 May 2019 08:10 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Sorry I meant "add to config\std_n8.asm"
However clock is clearly working which is good news and unlikley to be the problem.

R47 is shown in the 4314 schematics

/forum/index.php?t=getfile&id=1386&private=0

I'm having trouble getting my MK4 booting. Will get back to you if I have any luck and any more ideas.

Regards Phil







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Re: N8 (N8VEM) 4617 [message #6329 is a reply to message #6328] Sun, 19 May 2019 10:11 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
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I leave it(the std_N8.asm) for the moment because like you said unlikely the problem:
"Sorry I meant "add to config\std_n8.asm"
However clock is clearly working which is good news and unlikley to be the problem."

R47 4.7K
you are absolutely right.
I looked here at the older schematics:
https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=b oards:sbc:n8:printing_n8-2511-sch-12.pdf

I am gonna solder the Resistor in there.
and see if the floppy works better.

But don't worry and no hurry.
There is no rush.

I am glad it works almost, and I can already play around a little.
So thank you for how far we have come.

Thank you for contacting Andrew and Todd.

And I hope you get your MK4 back online.(not for me, but for your self I now how frustrating it can be)

Greeting Matthijs.
Re: N8 (N8VEM) 4617 [message #6332 is a reply to message #6329] Mon, 20 May 2019 02:39 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Hi Matthijs,

Can you please add these additional lines and report the output (cpu speed)

Thanks.

INITSYS3:
;
	LD	A,(CB_CRTDEV)		; GET CRT DISPLAY DEVICE                ***** add this line
	LD	(CB_CONDEV),A		; SAVE IT AS ACTIVE CONSOLE DEVICE      ***** and this line
	CALL	PRTSUM			; PRINT UNIT/DEVICE SUMMARY TABLE
	
        CALL	NEWLINE2		; ****** add this new line
	PRTX(STR_PLATFORM)		; ****** add this new line
	PRTS(" @ $")			; ****** add this new line
	LD	HL,(CB_CPUKHZ)		; ****** add this new line
	CALL	PRTD3M			; ****** add this new line
	PRTS("MHz$")			; ****** add this new line


; CHAIN TO OS LOADER
Re: N8 (N8VEM) 4617 [message #6333 is a reply to message #6332] Mon, 20 May 2019 06:08 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Hi Matthijs,

Can you please do a continuity test for each of the serial lines from the ZS180 pin all the way to your usb adapter? Thanks.

/forum/index.php?t=getfile&id=1391&private=0
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Re: N8 (N8VEM) 4617 [message #6334 is a reply to message #6333] Mon, 20 May 2019 07:18 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Hi Matthijs,

Please check the value of R42 - should be 2K2. Please check continuity to pin 47. Try bridging this resister so pin 47 is connected to ground. Pin 47 is DCD and needs to be low for comms to work I beleive. Regards Phil.

/forum/index.php?t=getfile&id=1392&private=0





  • Attachment: r4-DCD0.png
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[Updated on: Mon, 20 May 2019 07:29]

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Re: N8 (N8VEM) 4617 [message #6336 is a reply to message #6334] Mon, 20 May 2019 14:22 Go to previous messageGo to next message
jojoenco is currently offline  jojoenco
Messages: 27
Registered: April 2019
Junior Member
Wow faster reply than I thought.

And a little progress. (see: Serial gives output.jpg)

But first things first: CPU speed 18.432MHz

When I measure all the lines From the ZS180 they are all connected to the Max232 and from there to the Pins.

R42 =2.2K when I measure so that is oké.

And when I Bridge the Resistor so that pin 47 is connected to ground I get output.(Serial gives output.jpg)
Weird output but it is output on the serial line.
I tried Putty and Teraterm and I chanced to lower speed 9600 instead of 38400.
but the result stayed the same.

Then wen I type STAT CON:=TTY: I can type in Teraterm or Putty but when I type I get the same lines with letters.

But I think it is really good progress.

Greeting Matthijs
Re: N8 (N8VEM) 4617 [message #6337 is a reply to message #6336] Mon, 20 May 2019 16:23 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Hi Matthisj,

Does this output come when you boot up i.e. do you think it is the boot message?

Can you connect your DS0138 up again and confirm the output is a square wave and voltages are correct - 0 - 4/5v

Are you able to compare to usb side? Do they look the same?

Regards Phil.
Re: N8 (N8VEM) 4617 [message #6340 is a reply to message #6337] Tue, 21 May 2019 06:17 Go to previous messageGo to previous message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 396
Registered: November 2017
Senior Member
Hi Matthisj,

Keep R42 bridged to ground - I'm pretty sure that is correct.

Please try adding this bit of code after previous ones. Unfortunately I cannot test but it seems sane Smile Anyway report back what you get.

;	0 means	Z80
;	1 means Z180 - 80180
;	2 means Z180 S-class, SL1960 version
;	3 means Z180 advanced S-class, with Baud Rate Generator
;	Courtesy John Coffman UnaBIOS

cpu_type:
	ld	hl,0		; L = 0 means Z80
	ld	de,$0506	; 5 x 6
	mlt	de		; DE = 30 if Z180
	ld	a,e		; check if multiply happened
	cp	30
	jr	nz,cpux		; it is a Z80 if != 30

	inc	l		; flag Z180
        out0    (Z180_ASTC1L),d	; D = 0 at this point

        in0     a,(Z180_FRC)    ; supposedly only on S-class
        inc     a		; FF or 00 -> 0 or 1 (weak S-class or higher)
	add	a,l
	ld	l,a		; result to L and A

        in0     a,(Z180_ASTC1L) ; counter reg
        inc     a		; FF or 00 -> 0 or 1 (super-S)
	add	a,l
	ld	l,a
cpux:	ld	a,$30
	add	a,l
	PRTS(" Type: $")
	CALL	COUT

[Updated on: Tue, 21 May 2019 06:20]

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