I'm planning on de-hardcoding columns in VE a bit to add support
for screens narrower than 67 columns. There's a lot of hardcoding.
Let's begin with not using core's LIST anymore. This allows us to
spit 1-16 numbers only at startup.
Because that mode behaves exactly like in a regular TMS9918, a new
driver for TMS9918 has been added in blkfs and SMS' VDP now uses it.
Also, fix broken 5x7 font.
Also, rename CLRLN to NEWLN and make it clear that it's only called
on entering a new line. This way, we can set Z offset in there for
the TI-84+ LCD driver.
Rename ROWS to LINES (it's what VE uses). Also, don't use COLS and
LINES as immediates in the Grid subsystem: we expect those words to
be available at runtime.
If a line has a char below 0x20, we consider the line ended, we
stop the EMIT loop for this line and spit our NL.
This makes LIST stop wasting rows in environments with a tight
screen.
The '2' key on my PS/2 keyoard never worked on Collapse OS, I
wasn't sure why. I thought the keyboard was broken, but then I
tried another one, still broken. But it's only the '2'!
The KC sent is 0x1f. Is it a timing problem with the ATtiny? I
have yet to wire my prototype for logic probing. Meanwhile, let's
apply a band-aid.
Recipes contain bits and pieces of hardware-related knowledge, but
these bits feel sparse. I've been wanting to consolidate hardware-
related documentation for a while, but always fell at odds with the
recipes organisation.
We don't have recipes anymore, just a /doc/hw section that contains
hardware-related documentation which often translate to precise
instructions to run Collapse OS on a specific machine.
With this new organisation, I hope to end up with a better, more
solid documentation.
This would be useful, for example, to allow the assembler to write
straight to an AT28 EEPROM without going to RAM. This would be a
life saver in machines with tight RAM such as the SMS.
With KEY and EMIT being switch words, most of the high layer can
be defined before drivers.
In addition to this change, I've compacted core blocks which were
becoming quite sparse.
I think that when I added NL, I had troubles having access to CRLF's
address at boot time, which is why I had this system. But now that
CRLF is easily accessible during BOOT, we can simplify.
(and that will help us in the hopefully-upcoming change, which is
quite nice...)
also, verify all 3 first bytes of SPI commands. I'm not sure why
I wasn't doing that, probably because I was getting a lot of AVR
err and thought that only 2 bytes of the cmd were echoed. But now,
with a reliable SPI setup, verifying 3 bytes seems to work.
Adding a delay such as the 20ms one we have in AVR programmer's
initialization routine is tricky without a word like TICKS.
This implementation is highly inaccurate, but more accurate and
reliable than a "ballpark" DO..LOOP...
Also, move doc to doc/asm.txt.
Also, fix the pcat recipe which was broken since the overlay change.
I hadn't noticed it because I didn't have to rebuild the MBR.
The idea is to consider assemblers as "runtime" apps instead of
placing them in the "bootstrap" section of the blocks. These apps
will be used for much more than bootstrapping.
Moved its documentation to doc/asm.txt and made its code blocks
more compact.
The few extra bytes they save in the core aren't worth the extra
complexity. This was initially done in a context where I had
troubles keeping the RC2014 binary with SDC inside the 8K limit.
At this point, even with the few extra bytes we add here, we're at
7200 bytes, so I'd say we're fine.
With the Visual Editor, BROWSE is of dubious value. Even before that,
it was of dubious value. It's the only user of the CASE word, which
is also of dubious value: too complicated for its own good.
The CMD pattern used in VE is much better.
The ":" now takes care of scanning for ";". Conceptually, having
";" as an immediate word is slightly simpler than the approach in
this commit, but when bootstrapping is involved, this simpler
approach gets murkier.
Moreover, it got even murkier-er when trying to de-stabilize EXIT,
so here we are.
