Phil C's Raven build

[PhilC]

@dml well I managed to obtain 50 ram chips for just under a £1:each, I have some DACs and have a few quotes incoming for the W32i soon but expect them to be around £50 each from what I've had so far

[dml]

@dml well I managed to obtain 50 ram chips for just under a £1:each, I have some DACs and have a few quotes incoming for the W32i soon but expect them to be around £50 each from what I've had so far

That's encouraging! Interested to know how you get on with the quotes - I'd be up for one. (RAM also, if you're thinking of letting any go when the time comes).

I have some ISA cards to test here and there might be donors in that pile but I'm expecting them to (A) work or (B) not be interesting to harvest much useful. I have a small stack of old cards in storage for years too - but I think they will nearly all be PCI/AGP things. I'll need to go and have a dig soon.

[PhilC]

@dml yes happy to send with ram, lm385 and DAC if required.

Can't help you with the logic chips though as I only had enough F type to build one card.

[PhilC]

Whilst I was messing around with the graphics card I decided to fit the ESS 1868f sound card. Quickly booted up Doom but no sound was heard.

Doing a bit of a forum search and it looks like you need to set the built mixer. @agranlund did you manage to get that ESS app done? I'll have to dig out the datasheet and probably poke the mixer location with some better values before I can use it.

[agranlund]

So a bit of good news today.
The Excelgraph ET400/W32i works just fine on the Raven! It does some odd stuff if I select interleave in the bios menu but otherwise it works great so far. Other than a bit of ghosting, I'm very happy with it.

Wow!! So cool that you got the card running!


Is the interleave not working at all?
I wonder if there is a way to verify in Windows if interleave is working and that the driver has it enabled?
I'm absolutely just guessing now but I'm half assuming the windows driver would do some clever write/read tests to see if the particular hardware supports it and silently enable/disable it accordingly as to not confuse a regular consumer with techno-babble.

If I understand things correctly, and I can't say I'm confident I do, it looks like he's using the low bytes for regular access and the high bytes for interleaved access.

I'm wondering if that can cause trouble in comparison to using a second set of chips for the interleaved access.

Screenshot 2025-07-13 at 22.04.16.png

Screenshot 2025-07-13 at 22.20.40.png

CAS3:0 regular access, CAS7:4 only used when interleave mode is enabled.

The IS41C16257 and the IS41LV16257 has two CAS controls, LCAS and UCAS. The LCAS and UCAS inputs internally generate a CAS signal functioning in an identical manner to the single CAS input on the other 256K x 16 DRAMs.
The key difference is that each CAS controls its corresponding I/O tristate logic (in conjunction with OE and WE and RAS).
LCAS controls I/O0 - I/O7 and UCAS controls I/O8 - I/O15

The IS41C16257 and the IS41LV16257 CAS function is determined by the first CAS (LCAS or UCAS) transitioning LOW and the last transitioning back HIGH. The two CAS controls give the IS41C16257 both BYTE READ and BYTE WRITE cycle capabilities

[agranlund]

Whilst I was messing around with the graphics card I decided to fit the ESS 1868f sound card. Quickly booted up Doom but no sound was heard.

Doing a bit of a forum search and it looks like you need to set the built mixer. @agranlund did you manage to get that ESS app done? I'll have to dig out the datasheet and probably poke the mixer location with some better values before I can use it.

Ah no, I got sidetracked :)

As far as I can remember you can set the mixer both by using soundblaster registers or ESS registers.
The ESS registers allows more control and finer granularity compared to the backwards compatible soundblaster ones.
I believe AuxB was the wavetable volume and I think it's only available through ESS register.

If you just want to do something quick and dirty, or for testing, you may find c:\raven\mon.tos convenient for poking at the machine.
And if you have autoexec.prg you can always script a sequence of those to happen at startup in lieu of a dedicated program :)

For example, setting AuxB to 50% volume on left and right channels would look like this
(probably.. I'm not in front of the machine so I can't test it)
This is assuming your ESS is configured to live at $220, otherwise modify as necessary.

Code: Select all

mon.tos pb $81000224 $3a
mon.tos pb $81000225 $77

1. select register by writing it to (isa_io_base + ess_port + $4)
2. write to register by writing to (isa_io_base + ess_port + $5)

https://www.philscomputerlab.com/upload ... manual.pdf

[PhilC]

@agranlund I get a corrupt screen when using Win98, the same as I do when enabling interleaving on TOS.

I'm not going to mess too much with this card but if I can get some new et4000s will have a play with the next one. It looks like RA2 & 3 have the CAS and RAS lines on them, so I may be able to mess around with them to try and get Interleaving working

I think I'll use Mon.tos as you've suggested and may have a go at making an app. I've also got some plug and play ne2000 cards which need configuration, so hopefully they can be made to work with the Raven as well.

[PhilC]

Been learning a bit about ISA stuff today, mainly my ESS 1869F sound card which you can program in sound blaster mode or ESS mode.

So I've had to learn that to get it to do stuff, you program one register with a sound card register address and then the following register with the value you want in it. Great, I can do all that using mon.tos monitor program.

So in the case of setting the mixer as suggested by @agranlund you use register 4 & 5 as below

Code: Select all

pb $81000224 $22 ; the card sits at 220h and I'm selecting the master volume register.
Pb $81000225 !11101110 ; should be maximum volume 

I've done the same with the DAC register 04h and FM volume 26h but when I then play Doom or Tyrian there is no music or sound effects.

To all you sound blaster experts, what am I doing wrong? BTW, also tried the ESS specific registered. I'll test the card on a PC when I get a chance to rule out that being faulty.

[PhilC]

I answered my own question, the line out on the sound card was faulty.

So I've just got to work out how to get the Dreamblaster working now.

[PhilC]

Not having much luck with the wavetable card so far. It plays fine using the Picogus but I get nothing using either of my ES1689F sound cards. OPL plays fine on the ESS card but no sound from the Wavetable.

I've tried setting the volume of FM to maximum and then setting the ES689 serial to on, tried MPU401 on. I've even used an E-Wave wavetable board but still nothing.

It does say that for the ES689 to work that MCLK must show activity and MCD should be high. So I'll try those with the Oscilloscope. I'm sure Agranlund said he'd had the wavetable work by just adjusting mixer settings.