From d09de0a0d35266845a2738ce81654591f19a98df Mon Sep 17 00:00:00 2001
From: Virgil Dupras <hsoft@hardcoded.net>
Date: Sat, 2 Jan 2021 14:20:50 -0500
Subject: [PATCH] Integrate RDLN input buffer into sysvars

In the beginning of Collapse OS' Forth version, the readline sub-
system was optional. This is why we had this separate RDLN$ routine
and that the input buffer was allocated at boot time.

It's been a while since the RDLN system has been made mandatory, but
we still paid the complexity tax of this separation. Not anymore.
---
 arch/8086/pcat/blk.fs         |   2 +-
 arch/z80/rc2014/blk.fs        |   4 ++--
 arch/z80/sms/xcomp.fs         |   8 ++++----
 arch/z80/sms/xcompkbd.fs      |   8 ++++----
 arch/z80/sms/xcompsdc.fs      |   8 ++++----
 arch/z80/sms/xcomptextmode.fs |   8 ++++----
 arch/z80/ti84/xcomp.fs        |   8 ++++----
 arch/z80/trs80/xcomp.fs       |   2 +-
 arch/z80/z80mbc2/xcomp.fs     |   2 +-
 blk.fs                        |  23 ++++++++---------------
 cvm/common.fs                 |   2 +-
 cvm/forth.fs                  |   2 +-
 cvm/stage.bin                 | Bin 4908 -> 4852 bytes
 cvm/vm.h                      |   2 +-
 doc/hw/z80/ps2.txt            |   2 +-
 doc/hw/z80/sms/ps2.txt        |   2 +-
 doc/impl.txt                  |   8 +++++---
 emul/8086/xcomp.fs            |   2 +-
 emul/z80/xcomp.fs             |   2 +-
 19 files changed, 45 insertions(+), 50 deletions(-)

diff --git a/arch/8086/pcat/blk.fs b/arch/8086/pcat/blk.fs
index 97d86ee..ecae3a1 100644
--- a/arch/8086/pcat/blk.fs
+++ b/arch/8086/pcat/blk.fs
@@ -75,7 +75,7 @@ CODE AT-XY ( x y )
 ( ----- 612 )
 0xff00 CONSTANT RS_ADDR
 0xfffa CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xa0 - CONSTANT SYSVARS
 30 LOAD   ( 8086 asm )
 262 LOAD  ( xcomp ) 270 LOAD  ( xcomp overrides )
 445 461 LOADR ( 8086 boot code )
diff --git a/arch/z80/rc2014/blk.fs b/arch/z80/rc2014/blk.fs
index 8eb4d84..3ced90b 100644
--- a/arch/z80/rc2014/blk.fs
+++ b/arch/z80/rc2014/blk.fs
@@ -71,7 +71,7 @@ CODE SIOB>
 ( ----- 619 )
 ( RC2014 classic with MC6850 )
 0xff00 CONSTANT RS_ADDR        0xfffa CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xa0 - CONSTANT SYSVARS
 0x8000 CONSTANT HERESTART
 0x80 CONSTANT 6850_CTL 0x81 CONSTANT 6850_IO
 4 CONSTANT SPI_DATA 5 CONSTANT SPI_CTL 1 CONSTANT SDC_DEVID
@@ -88,7 +88,7 @@ PC ORG @ 8 + ! ( Update LATEST )
 ( ----- 620 )
 ( RC2014 classic with SIO )
 0xff00 CONSTANT RS_ADDR        0xfffa CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xa0 - CONSTANT SYSVARS
 0x8000 CONSTANT HERESTART
 0x80 CONSTANT SIOA_CTL   0x81 CONSTANT SIOA_DATA
 0x82 CONSTANT SIOB_CTL   0x83 CONSTANT SIOB_DATA
diff --git a/arch/z80/sms/xcomp.fs b/arch/z80/sms/xcomp.fs
index 2a6e769..84d7191 100644
--- a/arch/z80/sms/xcomp.fs
+++ b/arch/z80/sms/xcomp.fs
@@ -2,16 +2,16 @@
 0xdd00 CONSTANT RS_ADDR
 ( Memory register at the end of RAM. Must not overwrite )
 0xddca CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xb0 - CONSTANT SYSVARS
 0xc000 CONSTANT HERESTART
 0xbf   CONSTANT TMS_CTLPORT
 0xbe   CONSTANT TMS_DATAPORT
-SYSVARS 0x70 + CONSTANT GRID_MEM
-SYSVARS 0x73 + CONSTANT CPORT_MEM
+SYSVARS 0xa0 + CONSTANT GRID_MEM
+SYSVARS 0xa3 + CONSTANT CPORT_MEM
 0x3f   CONSTANT CPORT_CTL
 0xdc   CONSTANT CPORT_D1
 0xdd   CONSTANT CPORT_D2
-SYSVARS 0x74 + CONSTANT PAD_MEM
+SYSVARS 0xa4 + CONSTANT PAD_MEM
 5 LOAD  ( z80 assembler )
 262 LOAD  ( xcomp )
 524 LOAD  ( font compiler )
diff --git a/arch/z80/sms/xcompkbd.fs b/arch/z80/sms/xcompkbd.fs
index ea0bc08..50b1786 100644
--- a/arch/z80/sms/xcompkbd.fs
+++ b/arch/z80/sms/xcompkbd.fs
@@ -3,16 +3,16 @@
 0xdd00 CONSTANT RS_ADDR
 ( Memory register at the end of RAM. Must not overwrite )
 0xddca CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xb0 - CONSTANT SYSVARS
 0xc000 CONSTANT HERESTART
 0xbf   CONSTANT TMS_CTLPORT
 0xbe   CONSTANT TMS_DATAPORT
-SYSVARS 0x70 + CONSTANT GRID_MEM
-SYSVARS 0x73 + CONSTANT CPORT_MEM
+SYSVARS 0xa0 + CONSTANT GRID_MEM
+SYSVARS 0xa3 + CONSTANT CPORT_MEM
 0x3f   CONSTANT CPORT_CTL
 0xdc   CONSTANT CPORT_D1
 0xdd   CONSTANT CPORT_D2
-SYSVARS 0x74 + CONSTANT PS2_MEM
+SYSVARS 0xa4 + CONSTANT PS2_MEM
 5 LOAD  ( z80 assembler )
 262 LOAD  ( xcomp )
 524 LOAD  ( font compiler )
diff --git a/arch/z80/sms/xcompsdc.fs b/arch/z80/sms/xcompsdc.fs
index f0f69f3..b97b2f5 100644
--- a/arch/z80/sms/xcompsdc.fs
+++ b/arch/z80/sms/xcompsdc.fs
@@ -4,16 +4,16 @@
 0xdd00 CONSTANT RS_ADDR
 ( Memory register at the end of RAM. Must not overwrite )
 0xddca CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xb0 - CONSTANT SYSVARS
 0xc000 CONSTANT HERESTART
 0xbf   CONSTANT TMS_CTLPORT
 0xbe   CONSTANT TMS_DATAPORT
-SYSVARS 0x70 + CONSTANT GRID_MEM
-SYSVARS 0x73 + CONSTANT CPORT_MEM
+SYSVARS 0xa0 + CONSTANT GRID_MEM
+SYSVARS 0xa3 + CONSTANT CPORT_MEM
 0x3f   CONSTANT CPORT_CTL
 0xdc   CONSTANT CPORT_D1
 0xdd   CONSTANT CPORT_D2
-SYSVARS 0x74 + CONSTANT PS2_MEM
+SYSVARS 0xa4 + CONSTANT PS2_MEM
 5 LOAD  ( z80 assembler )
 262 LOAD  ( xcomp )
 524 LOAD  ( font compiler )
diff --git a/arch/z80/sms/xcomptextmode.fs b/arch/z80/sms/xcomptextmode.fs
index a436312..9dc74b7 100644
--- a/arch/z80/sms/xcomptextmode.fs
+++ b/arch/z80/sms/xcomptextmode.fs
@@ -4,16 +4,16 @@
 0xdd00 CONSTANT RS_ADDR
 ( Memory register at the end of RAM. Must not overwrite )
 0xddca CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xb0 - CONSTANT SYSVARS
 0xc000 CONSTANT HERESTART
 0xbf   CONSTANT TMS_CTLPORT
 0xbe   CONSTANT TMS_DATAPORT
-SYSVARS 0x70 + CONSTANT GRID_MEM
-SYSVARS 0x73 + CONSTANT CPORT_MEM
+SYSVARS 0xa0 + CONSTANT GRID_MEM
+SYSVARS 0xa3 + CONSTANT CPORT_MEM
 0x3f   CONSTANT CPORT_CTL
 0xdc   CONSTANT CPORT_D1
 0xdd   CONSTANT CPORT_D2
-SYSVARS 0x74 + CONSTANT PS2_MEM
+SYSVARS 0xa4 + CONSTANT PS2_MEM
 5 LOAD  ( z80 assembler )
 262 LOAD  ( xcomp )
 523 LOAD  ( font compiler )
diff --git a/arch/z80/ti84/xcomp.fs b/arch/z80/ti84/xcomp.fs
index e13e783..9afca8c 100644
--- a/arch/z80/ti84/xcomp.fs
+++ b/arch/z80/ti84/xcomp.fs
@@ -1,10 +1,10 @@
 0xbf00 CONSTANT RS_ADDR
 0xbffa CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xb0 - CONSTANT SYSVARS
 0x8000 CONSTANT HERESTART
-SYSVARS 0x70 + CONSTANT LCD_MEM
-SYSVARS 0x72 + CONSTANT GRID_MEM
-SYSVARS 0x75 + CONSTANT KBD_MEM
+SYSVARS 0xa0 + CONSTANT LCD_MEM
+SYSVARS 0xa2 + CONSTANT GRID_MEM
+SYSVARS 0xa5 + CONSTANT KBD_MEM
 0x01 CONSTANT KBD_PORT
 5 LOAD  ( z80 assembler )
 262 LOAD  ( xcomp )
diff --git a/arch/z80/trs80/xcomp.fs b/arch/z80/trs80/xcomp.fs
index f0d37ec..3b9b8d3 100644
--- a/arch/z80/trs80/xcomp.fs
+++ b/arch/z80/trs80/xcomp.fs
@@ -1,6 +1,6 @@
 0xff00 CONSTANT RS_ADDR
 0xfffa CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xa0 - CONSTANT SYSVARS
 0 CONSTANT HERESTART
 5 LOAD   ( z80 assembler )
 262 LOAD ( xcomp )
diff --git a/arch/z80/z80mbc2/xcomp.fs b/arch/z80/z80mbc2/xcomp.fs
index b90cdd8..645e861 100644
--- a/arch/z80/z80mbc2/xcomp.fs
+++ b/arch/z80/z80mbc2/xcomp.fs
@@ -1,5 +1,5 @@
 0xff00 CONSTANT RS_ADDR        0xfffa CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xa0 - CONSTANT SYSVARS
 0 CONSTANT HERESTART
 5 LOAD    ( z80 assembler )
 262 LOAD  ( xcomp )
diff --git a/blk.fs b/blk.fs
index 4c193b5..5b9d3a6 100644
--- a/blk.fs
+++ b/blk.fs
@@ -1682,14 +1682,13 @@ with "390 LOAD"
 : H@ HERE @ ;
 : FIND ( w -- a f ) CURRENT @ SWAP _find ;
 : IN> 0x30 RAM+ ; ( current position in INBUF )
-: IN( 0x32 RAM+ @ ; ( points to INBUF )
-: IN) 0x40 ( buffer size ) IN( + ; ( INBUF's end )
+: IN( 0x60 RAM+ ; ( points to INBUF )
 : IN$ 0 IN( DUP IN> ! ! ; ( flush input buffer )
 : QUIT
     (resRS) 0 0x08 RAM+ ! ( C<* override ) IN$
     LIT" (main)" FIND DROP EXECUTE
 ;
-1 33 LOADR+
+1 31 LOADR+
 ( ----- 354 )
 : ABORT (resSP) QUIT ;
 : = CMP NOT ; : < CMP -1 = ; : > CMP 1 = ;
@@ -1978,7 +1977,7 @@ SYSVARS 0x55 + :** KEY?
 : RDLN ( Read 1 line in input buff and make IN> point to it )
     IN$ BEGIN
     ( buffer overflow? same as if we typed a newline )
-    IN> @ IN) 1- = IF CR ELSE KEY THEN ( c )
+    IN> @ IN( - 0x3e = IF CR ELSE KEY THEN ( c )
     DUP BS? IF
         IN> @ IN( > IF -1 IN> +! BS EMIT THEN SPC> BS EMIT
     ELSE DUP LF = IF DROP CR THEN ( same as CR )
@@ -1996,13 +1995,6 @@ SYSVARS 0x55 + :** KEY?
     ( update C<? flag )
     IN> @ C@ 0 > 0x06 RAM+ !  ( 06 == C<? ) ;
 ( ----- 381 )
-( Initializes the readln subsystem )
-: RDLN$
-    H@ 0x32 ( IN(* ) RAM+ !
-    IN) IN( - ALLOT IN$
-    ['] RDLN< ['] C<* **!
-    1 0x06 RAM+ !  ( 06 == C<? ) ;
-( ----- 382 )
 : LIST
     BLK@
     16 0 DO
@@ -2012,7 +2004,7 @@ SYSVARS 0x55 + :** KEY?
         LOOP
         NL>
     LOOP ;
-( ----- 383 )
+( ----- 382 )
 : INTERPRET
     BEGIN
     WORD DUP @ 0x0401 = ( EOT ) IF DROP EXIT THEN
@@ -2028,7 +2020,7 @@ SYSVARS 0x55 + :** KEY?
   is to check whether we're restoring to "_", the word above.
   if yes, then we're in a nested load. Also, the 1 in 0x06 is
   to avoid tons of "ok" displays. )
-( ----- 384 )
+( ----- 383 )
 : LOAD
     BLK> @ >R ( save restorable variables to RSP )
     0x08 RAM+ @ >R  ( 08 == C<* override )
@@ -2045,7 +2037,7 @@ SYSVARS 0x55 + :** KEY?
     ELSE ( not nested )
         R> 0x08 RAM+ ! R> DROP ( BLK> )
     THEN ;
-( ----- 385 )
+( ----- 384 )
 : LOAD+ BLK> @ + LOAD ;
 ( b1 b2 -- )
 : LOADR 1+ SWAP DO I DUP . SPC> LOAD LOOP ;
@@ -2062,7 +2054,8 @@ SYSVARS 0x55 + :** KEY?
     ['] (boot<) ['] C<* **!
     ( boot< always has a char waiting. 06 == C<?* )
     1 0x06 RAM+ ! INTERPRET
-    RDLN$ LIT" _sys" [entry]
+    ['] RDLN< ['] C<* **! IN$
+    LIT" _sys" [entry]
     LIT" Collapse OS" STYPE NL> (main) ;
 XCURRENT @ _xapply ORG @ 0x04 ( stable ABI BOOT ) + !
 1 4 LOADR+
diff --git a/cvm/common.fs b/cvm/common.fs
index e50bfc9..f4531cc 100644
--- a/cvm/common.fs
+++ b/cvm/common.fs
@@ -2,7 +2,7 @@
   binaries. )
 0xff00 CONSTANT RS_ADDR
 0xfffa CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xb0 - CONSTANT SYSVARS
 0 CONSTANT HERESTART
 : CODE ( natidx -- ) (entry) 0 C, C, ;
 VARIABLE ORG
diff --git a/cvm/forth.fs b/cvm/forth.fs
index 11b9e70..06cd97b 100644
--- a/cvm/forth.fs
+++ b/cvm/forth.fs
@@ -3,7 +3,7 @@
     DROP COLS /MOD 6 PC! ( y ) 5 PC! ( x ) ;
 : CELL! ( c pos -- ) 0 CURSOR! 0 PC! ;
 
-SYSVARS 0x70 + CONSTANT GRID_MEM
+SYSVARS 0xa0 + CONSTANT GRID_MEM
 402 403 LOADR ( Grid )
 390 LOAD  ( xcomp core high )
 (entry) _
diff --git a/cvm/stage.bin b/cvm/stage.bin
index b50c81647c0287e9076a5dff78b8ce6f07f7398e..5fc72b96459bdea38313395f0aa2b78ce9045807 100644
GIT binary patch
delta 2678
zcmYjTYfM|`8GgTW@j1S6&7~2?fnYoXxj<HJRUHGtU?{|~kvTNZk}N<=)Ts%M5;BCk
z#x3<CMOD<%PjZA5#hK7V)^3?9WlQ^K%a5(?q)og0Nu);8{s79FO<RaMMPg*ndk#po
zWS{T6_sjFXpMUm^Cy_0L&v&X`(EnV+C+BnIqb*+wG4#IjzHgM)ghd1Crhxo~5-D6)
z2FcTWX6$>DEqSFxQ)E$hB9pZvq>I<YZN;JvlZ1Fjtbr4Ek2k~$=$$@?KJUD=$Ni*;
z1U)M}V^#;hJysl@4lmBnoO63;hmTYdRGHBk2cro(3VlS+lqJY4f!xs<@7PM(2E9&Q
z5_NJ~?GtaxU#q+D`*$^l-#Trt$jbq(PI%;m_RYrQT3WLxd3eCCCQV;hAGVJUB~9c|
zQl%KBk~$|p(b6w0X>$-urx3de4@0QMesP7`$TO!!D43ui&1nhp;TP7j*(Qix(;mo9
zy<SA+clDi(QQe~E>B&<qbufNS8>GsH>HN7@8z%Ep4X5%KCSQ%p>-rAmu_8aw>-$UU
zP1-M{C{u#=(u&eX>LOm35YkQR7Ye*z)z{$PU!q%Je5G0xqop#GHWhR!F3Wn)w(1q-
zCakC^CNrb7BKthy=W=Qrc@xx5Cc0XLz!<)#C@0_cgvE;dpQrKLhdf0Jve>8Odf;d@
z`YYVW=!?8M56zQj$48KBkrqW5*4xKfbx$FOPJK<$^;4#K;VS>hRc<~zcJBN{%LEx>
zy9X&+bjf}E&3*h<cZe5Ix}JC!*EB&Mls*i{J@M8GQuX8OJ#pPZkm)e45Ia^p7v%>=
zxbRceQbG{k(-?%zC4=*9bjqoh0GT^Rgub-s$Z(eh+e=y$5hOEqmme^?tua>dw#R+D
zV_0Noj%2dELGqyDC1P{S#u^&(#CQa!|3WpU$LpLZE1Y4GDKjwAZiYm=2`^9u#&BK~
zHD(b?ZDf2(2f?~Ytzr@3ai8`<lRLKT*jz4CyJ?DB&}tQ|;W=nVNNtxtHxsqCnMa6G
zo~<uTPFuYo6>k&p9rd0mq_r~b^jdUmVsh%-%!w^1a!Gwt{egE(8BxN*6br^3gU?)`
zW=E){5kj^pq1BU3cH2o#^<$t!L8&ZyxjQ@1ok%5Xftk-8D$h<|CflFH^mxQFvMK_O
z46}l)^-XMDfL2c?J#2TU?Wm)*U<}GDzL2oxhrTK0sZZ|m??kAIDaAvOZ-{&NwJ4D~
zv@3#Q-SdUTXZTJ5fy{@y)X4Bl&tZlhf{c`t{;%mA+y<Q@u@=va)8tV<6GGxwjv3c9
zZ0llv!{U+Dzz{Ok#8Y2_NR#5Y_G3T#1!`~CR^&A={QjrdfBnb|Ju4xW2WpJ|!?_I|
zt%v5Qzf3cJ_L7voKs?D?z?~gGkK>$nLsW=$1d^Z^v9dNI<JIv`i@IWHU|2*0zz_G5
zrM!@m?*{f1@_{*xzZUJw?Er>X#nr%7mgFVMk}+5>($&B!){lnBM&URt9ywyG+AlGw
z|1LqybXX;|NJ|jBNbZ0l7e?HihTTD!vfh!yLoXvA9(0qoi*kWc#hYi8?gnDCX3?SK
z(JrK{|70B}55RsP*v9n4Fvf-#0eX)KE7M&J&?5|4wl|gD4x87Nw*b5M6cgy^bY{?V
z9|cf*gGI{1M!n1C>Y$}>DIV>vHdoMA`2o3xBK-jtozmS$#+)^4gwP%qF4BFl%Nw&;
zdJo<hF6=%22D;6%`w?Cn`CJ9KJ{@$a5?6@3Sy&}CFl@IW;2HF;Q03IEALGfH`RFks
zP*=66Q}2U-L<L}@ILw1+PnlepuyDQ8Y3G6f5E(Jcq{rwsU!rz0JCse@uaFn>#tlo5
z*v!tNJT5(qdY=*5O6nAy!IEhscpM}p|N1p_`M(w468GfZ%5ZuH$aI%R2sVCK!F^kE
zin5u|Y();i@LCB8KJfw#iGE1C8<T4q$We)MG$XH9hI)8<6!EYEmB@7WW~)%V#f`*@
z#ECzwh|!Y`?rsYM;%bzgx#JqVE7vQZ=iz?7s+}JbRjp!H{;2B3LcA)0&P4#h&npvj
zAjl^U`l1oh<`I$`+$<>nz@^Gm{-2?pJU??@dI!nhlRtfW?Ckl8hRiVPpr@*E?X}LL
z@VuooY$@J2vDVfqK#@uM2I=JZE3ds?Lj`>Upw3?or$3d0WQ?C{$bbLTX<XRYr@fgb
znnft1w1D-<X=a8hsR&BUp_sy`=53f7u+#4UjRffIw>dy>i$M}Cw)qAY#aD==5>xuI
zcV65vxXpt$i37~St)0MVuu>l7uPM^+O*DLp0LleiN_wA>tB%kg0hPWkCz>|L_q^bZ
zYrm9C*CL`KjVYH^Lsr++4lfwY`%Cqha?63R-MHO}dC<|52;ehZS1f-E4QhqVzQ%f3
z7BvaFrg0$7zqiI}x+KD&Jx~_pbWLbC*I+Z_k+eOK+D1P_Dco>28OLgn_^kX*&5o93
lGgrM?k7GTV!$Sk9<cV!`8J7b)ITk(Pqj&I<lcIL_{{gfQM$G^K

delta 2755
zcmY*bZA@F|6+Z9%u&+O`!9Y?}JGdB^kB}I;uf~G_1}B9$HnPnEVk|K!Nmo)F1=h5i
zRMXVmI*pAquf*mmlJf&4A)68*HT>$&sMS(MlNL>rnn~Lq`Xgk`qE%ZGp>EH)*X+a6
zz4v|3d!F-s&g(D3zj?ln@Vi(&tQ)nwGJmhG)olu~a6!2cc!9P=Ncd?e+2$ct#Hf#!
z6vZSod*nqW+_<I;ldbi&-1leO^2##Jlb`xysdP3>x_Cu=BLAZ7EId{GwBJcWydz42
zH=W%sQXuVL1)qwe9^UEd7O>qt4y=9Vx^sVz6H0^TW`8#y#7Lnv@~InO*#LXb{_dW7
z(kk@5pyL5OIW$rSXqlF=k*}*?7w6@#)#vcOqek&Iv^{}yP<=Qx$SQUU=Ic)+Qdu|b
z_A3oCt-a8c*K(Sl;)jQ_HKgfxzsh9CN8$z;R#hpE(W<&4FKfwfJ=RvhmQ27!4$%l=
z)+K&U5wfjlVXBHz6|HD7a^ekX>2x#LZfFnXZoN@N<sp4nQ&jg;>)F{8ZO=mZ4Q-gb
z!L#`@F9&Dy^T8AOAI!cSl|R!P6kU~<^~S=gdX>6_gm*F8Lr;|msaLSwfJs;BpirRw
zn!W}7u4TH80|(SbX`>9#Hb9r+qFO>8kDfk00&|LV1*jOcK-^V`RT1m${RXitApCR_
z#F8Ae`JS0kBjkutCmA3Yfym)GK{ImJ77|b8eOuEvzh^5_kl8*a%LcYrqu;~8DBU|(
zQ9m_WQ6GZ(&MAg=ygH+@%Krc@J!L8h3;a6^+<H29W^TG|n(U(8h9LN<WPKi4pFip*
z@jV20pu3l&9wS?&pa;6!QPBFLT(IvD@5^7>Lxqo2zY>5q9Zgm6zGP>wn#}O(TphRV
zVcPW5kxZ{2k{)YO=!>Vay)KmBCmL5Zb{*F4w%t$J)R9zru!?NRz%sG8C-yBQ$ZkA<
zZ(ktvXQ!SuZSue-ROvp$Jvv|n#DD=UfTHHGz9Pa#5uga!Kc)<hu2Q?W0`oXcdx7MH
zJ+ZUQ&&xDm7~(om?Sc`uj1eYvKz?AvYEK$@nAl>V3%@Wpy6SuKq0ubP$vVetg`9@!
zaQJCrdUpQIo0D}2>8g5OU2^1<Q6(e{v2MR@=QRhY)nsaG0@F$3GEf8Qcz-s|u6~M|
zP!K9VeWyP?)E`U4Yf&NhOe*)%fmHfn9NlCSPvBJ%<;hi6xZs?wUk7L)mCR)Oli3y%
zv~Hi2KXeAfN%<@1yyA9Ak82k!tv96D0{N1-kGG#<i9^qY5v%*okoXMGJj#vFp)E0*
zdFdIn)E3C_c+B-bn7$pr6p2yXLS~NVTucav-<o19(U7fUY*`YIB!))ds3zR57?CDL
zUi;96bb&h9TMxHNVwcP9I)*mvf=2r?Y<Z|g=@I)jGTsQ}oU2TWF4i(8|LN+E^H8uF
z1tRxgMqCmeQRC+7+lNV4v5Y6lU;We@MgBq}>PGo+Dw)dxF8PMLW9FQDMdQa$d&e43
z!haXn+}D_sM=x_mA-zb~+%}yXkw;jOLgInRX47w?E&sL*Hp4txRg3f(W9u!lx)Hu`
z!L4W*CAHF9wX1N~9i=Tl9g2_l!ZH01UtwiKMJKBwOpj&I8$4Q&V6;)0?xIT`pp(*r
ziR4a1Vog~<ZCz5Xn+dRO!bSB+RgtEFZ{(vTh5bj;7L*3<E~cza=XaQbMf$UbYsC!C
zCVXPQ7!g1Mn7K%sP*$!q+XqX~#09~cyU!w@%-aRiBIL9HP+h39s1kRJH7K?r&7FYc
zlo;`Kh{98r6hq_++8RhtFyG&|zo?Ze!-X-4p-eUc2N#jiYBQJz(Xt!}C+YA=wdqka
z34N#&4{Av<5Brd_GFi35%#CLH%}WH;$z}9;tsbQh`8v+V)6tQ1JbRoRXhKe7j09Y+
zluKUW7PpOKW~uYEfWZ?XXdEUbKXXH?l{Y=#5clP#Clp#lxmtrH01<XCr=OktuRphB
zm$%W)qTOS-PseCce%Bi?xN#J*+biGp)<4hg?Dj_KOE{nEA58D|qZcfWve{zn*&X?j
z_iNn8kG!4y301d?TQXU_ukcoN3@Ln(FG;MDRlH(T{y(s{JRP24(vHr(Id|DHOs;|a
zsZ+VrbJM|820rP(sKzzd{sw}`Q%J)U;*k<<Z?8rbGD)wHj!qqaWyXh;TBWH7SzV*y
zpGbtf!(^X26U@JU;uJ1u%*(-4Go3?Rj?p^CA3K*C@lp|#s7WzIZw*ho#85VA{SS$O
z&U#zj^tKo#(RR}K5hlSuV2KxP_^G2LZreFyIQurA;F6A^DGChABgnoY{fTGyJRx`M
zNT5D$KVK83J4pM1UelV0sk<b2qGn%;Cu?C*k#fpKwYR2>>j76$B7@1xc80;roDN?O
zjb>Wfw9`BpHl;|I^BFFuJq*8&EHQj<QzI1Z^Tp_f#&((i=$dNi$6^AshswI_^#x#Y
z4t-z+U^JN>O6;I_q0zE#`(VO{INb91Y0?Jwxqx^S9v&G=#69#ATm$E8wnH{ip-=9h
gpW=WOPqa)r=^c~Hns^xY&B2yn{6MBp-t#s58?cy0!vFvP

diff --git a/cvm/vm.h b/cvm/vm.h
index 21b577e..4b6b588 100644
--- a/cvm/vm.h
+++ b/cvm/vm.h
@@ -3,7 +3,7 @@
 
 #define SP_ADDR 0xffff
 #define RS_ADDR 0xff00
-#define SYSVARS RS_ADDR-0x80
+#define SYSVARS RS_ADDR-0xb0
 #define MEMSIZE 0x10000
 
 typedef uint8_t byte;
diff --git a/doc/hw/z80/ps2.txt b/doc/hw/z80/ps2.txt
index b30ea03..706a05e 100644
--- a/doc/hw/z80/ps2.txt
+++ b/doc/hw/z80/ps2.txt
@@ -68,7 +68,7 @@ First, we need a "(ps2kc)" routine (see doc/protocol.txt). In
 this case, it's easy, it's ": (ps2kc) 8 PC@ ;". Then, we can
 load PS/2 subsystem. You add "411 414 LOADR". Then, at
 initialization, you add "PS2$".  You also need to define PS2_MEM
-at the top. You can probably use "SYSVARS + 0x7a".
+at the top. You can probably use "SYSVARS + 0xaa".
 
 The PS/2 subsystem provides "(key)" from "(ps2kc)".
 
diff --git a/doc/hw/z80/sms/ps2.txt b/doc/hw/z80/sms/ps2.txt
index 1acfad7..a9edc40 100644
--- a/doc/hw/z80/sms/ps2.txt
+++ b/doc/hw/z80/sms/ps2.txt
@@ -113,7 +113,7 @@ it with /cvm/avra.sh.
 
 We start with the base SMS xcomp and add a few things:
 
-1. at the top: "SYSVARS 0x72 + CONSTANT PS2_MEM"
+1. at the top: "SYSVARS 0xa2 + CONSTANT PS2_MEM"
 2. After VDP load: "621 LOAD : (ps2kc) (ps2kcB) ;" (that binds
    us to port B)
 3. Right after: "411 414 LOADR" (that gives us "(key)")
diff --git a/doc/impl.txt b/doc/impl.txt
index 1f086fb..724284d 100644
--- a/doc/impl.txt
+++ b/doc/impl.txt
@@ -153,6 +153,9 @@ fact, they're mostly referred to directly as their numerical
 offset along with a comment indicating what this offset refers
 to.
 
+SYSVARS occupy 0xa0 bytes in memory in addition to driver mem-
+ory, which typically follows SYSVARS.
+
 This system is a bit fragile because every time we change those
 offsets, we have to be careful to adjust all system variables
 offsets, but thankfully, there aren't many system variables.
@@ -167,9 +170,8 @@ SYSVARS   FUTURE USES          +3c       BLK(*
 +0c       C<*                  +53       EMIT ialias
 +0e       WORDBUF              +55       KEY? ialias
 +2e       BOOT C< PTR          +57       FUTURE USES
-+30       IN>
-+32       IN(*                 +70       DRIVERS
-+34       BLK@*                +80       RAMEND
++30       IN>                  +60       INPUT BUFFER
++32       FUTURE USES          +a0       DRIVERS
 +36       BLK!*
 +38       BLK>
 +3a       BLKDTY
diff --git a/emul/8086/xcomp.fs b/emul/8086/xcomp.fs
index f6e294b..e1b6839 100644
--- a/emul/8086/xcomp.fs
+++ b/emul/8086/xcomp.fs
@@ -1,6 +1,6 @@
 0xff00 CONSTANT RS_ADDR
 0xfffa CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xa0 - CONSTANT SYSVARS
 30 LOAD   ( 8086 asm )
 262 LOAD  ( xcomp ) 270 LOAD  ( xcomp overrides )
 445 461 LOADR ( 8086 boot code )
diff --git a/emul/z80/xcomp.fs b/emul/z80/xcomp.fs
index 571fa4f..224de01 100644
--- a/emul/z80/xcomp.fs
+++ b/emul/z80/xcomp.fs
@@ -1,6 +1,6 @@
 0xff00 CONSTANT RS_ADDR
 0xfffa CONSTANT PS_ADDR
-RS_ADDR 0x80 - CONSTANT SYSVARS
+RS_ADDR 0xa0 - CONSTANT SYSVARS
 0 CONSTANT HERESTART
 5 LOAD  ( z80 assembler )
 262 LOAD  ( xcomp )