From 456cb97fac39c581feb21223782feedd8f1d9b6e Mon Sep 17 00:00:00 2001
From: UzixLS <uzix.ls@gmail.com>
Date: Mon, 31 Jan 2022 21:39:26 +0300
Subject: [PATCH] add support for ZC SD card controller; replace NO-OS divmmc
 mode with ZC

---
 fpga/rtl/common.sv                |   1 -
 fpga/rtl/divmmc.sv                |  33 ++++++++++++++++++++++--------
 fpga/rtl/magic.sv                 |  11 +++++-----
 fpga/rtl/top.sv                   |  15 ++++++++------
 rom/Makefile                      |   6 +++---
 rom/{dvmen3e0.rom => zcen3e0.rom} | Bin
 rom/{dvmen3e1.rom => zcen3e1.rom} | Bin 16384 -> 16384 bytes
 rom/{dvmen3e2.rom => zcen3e2.rom} | Bin 16384 -> 16384 bytes
 rom/{dvmen3e3.rom => zcen3e3.rom} | Bin 16384 -> 16384 bytes
 rom_src/config.asm                |   2 +-
 rom_src/main.asm                  |  13 ++++++------
 rom_src/menu_structure.asm        |  16 +++++++--------
 rom_src/strings.asm               |   7 +++++--
 13 files changed, 63 insertions(+), 41 deletions(-)
 rename rom/{dvmen3e0.rom => zcen3e0.rom} (100%)
 rename rom/{dvmen3e1.rom => zcen3e1.rom} (90%)
 rename rom/{dvmen3e2.rom => zcen3e2.rom} (96%)
 rename rom/{dvmen3e3.rom => zcen3e3.rom} (93%)

diff --git a/fpga/rtl/common.sv b/fpga/rtl/common.sv
index 91218f5..ec75b2c 100755
--- a/fpga/rtl/common.sv
+++ b/fpga/rtl/common.sv
@@ -2,7 +2,6 @@ package common;
     typedef enum { MACHINE_S48, MACHINE_S128, MACHINE_S3, MACHINE_PENT } machine_t;
     typedef enum { TURBO_NONE, TURBO_4, TURBO_5, TURBO_7, TURBO_14 } turbo_t;
     typedef enum { PANNING_MONO, PANNING_ABC, PANNING_ACB } panning_t;
-    typedef enum { DIVMMC_OFF, DIVMMC_ON, DIVMMC_NOOS } divmmc_t;
 endpackage
 
 
diff --git a/fpga/rtl/divmmc.sv b/fpga/rtl/divmmc.sv
index 71ae4b3..e360e0d 100755
--- a/fpga/rtl/divmmc.sv
+++ b/fpga/rtl/divmmc.sv
@@ -6,11 +6,13 @@ module divmmc(
     input ck7,
     input en,
     input en_hooks,
+    input en_zc,
 
     cpu_bus bus,
     output [7:0] d_out,
     output d_out_active,
 
+    input sd_cd,
     input sd_miso,
     output sd_mosi,
     output reg sd_sck,
@@ -61,21 +63,20 @@ always @(posedge clk28 or negedge rst_n) begin
     end
 end
 
-reg spi_rd;
 reg conmem, mapram;
 wire port_e3_cs = en && bus.ioreq && bus.a_reg[7:0] == 8'hE3;
 wire port_e7_cs = en && bus.ioreq && bus.a_reg[7:0] == 8'hE7;
 wire port_eb_cs = en && bus.ioreq && bus.a_reg[7:0] == 8'hEB;
+wire port_57_cs = en_zc && bus.ioreq && bus.a_reg[7:0] == 8'h57;
+wire port_77_cs = en_zc && bus.ioreq && bus.a_reg[7:0] == 8'h77;
 always @(posedge clk28 or negedge rst_n) begin
     if (!rst_n) begin
-        spi_rd <= 0;
         page <= 0;
         mapram <= 0;
         conmem <= 0;
         sd_cs <= 1'b1;
     end
     else begin
-        spi_rd <= port_eb_cs && bus.rd;
         if (port_e3_cs && bus.wr) begin
             page <= bus.d_reg[3:0];
             mapram <= bus.d_reg[6] | mapram;
@@ -84,6 +85,22 @@ always @(posedge clk28 or negedge rst_n) begin
         if (port_e7_cs && bus.wr) begin
             sd_cs <= bus.d_reg[0];
         end
+        else if (port_77_cs && bus.wr) begin
+            sd_cs <= bus.d_reg[1] | ~bus.d_reg[0];
+        end
+    end
+end
+
+reg spi_rd, zc_rd;
+wire [7:0] zc_data = {7'b0000000, sd_cd};
+always @(posedge clk28 or negedge rst_n) begin
+    if (!rst_n) begin
+        spi_rd <= 0;
+        zc_rd <= 0;
+    end
+    else begin
+        spi_rd <= (port_eb_cs || port_57_cs) && bus.rd;
+        zc_rd <= port_77_cs && bus.rd;
     end
 end
 
@@ -93,7 +110,7 @@ assign cpuwait = ~spi_cnt[3];
 always @(posedge clk28 or negedge rst_n) begin
     if (!rst_n)
         spi_cnt <= 0;
-    else if (port_eb_cs && (bus.rd || bus.wr))
+    else if ((port_eb_cs || port_57_cs) && (bus.rd || bus.wr))
         spi_cnt <= 4'b1110;
     else if (spi_cnt_en && ck7)
         spi_cnt <= spi_cnt + 1'b1;
@@ -103,7 +120,7 @@ reg spi_mosi_en;
 always @(posedge clk28 or negedge rst_n) begin
     if (!rst_n)
         spi_mosi_en <= 0;
-    else if (port_eb_cs && bus.wr)
+    else if ((port_eb_cs || port_57_cs) && bus.wr)
         spi_mosi_en <= 1'b1;
     else if (!spi_cnt_en)
         spi_mosi_en <= 0;
@@ -114,7 +131,7 @@ assign sd_mosi = spi_mosi_en? spi_reg[7] : 1'b1;
 always @(posedge clk28 or negedge rst_n) begin
     if (!rst_n)
         spi_reg <= 0;
-    else if (port_eb_cs && bus.wr)
+    else if ((port_eb_cs || port_57_cs) && bus.wr)
         spi_reg <= bus.d_reg;
     else if (spi_cnt[3] == 1'b0 && ck7)
         spi_reg[7:0] <= {spi_reg[6:0], sd_miso};
@@ -136,7 +153,7 @@ assign ramwr_mask =
     (!bus.a[13] || page == 4'b0011) &&
     !conmem && automap && mapram;
 
-assign d_out_active = spi_rd;
-assign d_out = spi_reg;
+assign d_out_active = zc_rd | spi_rd;
+assign d_out = zc_rd? zc_data : spi_reg;
 
 endmodule
diff --git a/fpga/rtl/magic.sv b/fpga/rtl/magic.sv
index 0470d54..f280da4 100755
--- a/fpga/rtl/magic.sv
+++ b/fpga/rtl/magic.sv
@@ -13,7 +13,6 @@ module magic(
 
     input magic_button,
     input pause_button,
-    input sd_cd,
     input div_automap,
 
     output reg magic_mode,
@@ -25,7 +24,8 @@ module magic(
     output turbo_t turbo,
     output panning_t panning,
     output reg joy_sinclair,
-    output divmmc_t divmmc_en,
+    output reg divmmc_en,
+    output reg zc_en,
     output reg ulaplus_en,
     output reg ay_en,
     output reg covox_en,
@@ -80,7 +80,8 @@ always @(posedge clk28 or negedge rst_n) begin
         turbo <= TURBO_NONE;
         panning <= PANNING_ABC;
         joy_sinclair <= 0;
-        divmmc_en <= DIVMMC_NOOS;
+        divmmc_en <= 0;
+        zc_en <= 1'b1;
         ulaplus_en <= 1'b1;
         ay_en <= 1'b1;
         covox_en <= 1'b1;
@@ -93,14 +94,14 @@ always @(posedge clk28 or negedge rst_n) begin
         8'h04: panning <= panning_t'(bus.d_reg[1:0]);
         8'h07: joy_sinclair <= bus.d_reg[0];
         8'h08: ay_en <= bus.d_reg[0];
-        8'h09: divmmc_en <= divmmc_t'(bus.d_reg[1:0]);
+        8'h09: {zc_en, divmmc_en} <= bus.d_reg[1:0];
         8'h0a: ulaplus_en <= bus.d_reg[0];
         8'h0b: {soundrive_en, covox_en} <= bus.d_reg[1:0];
     endcase
 end
 
 reg config_rd;
-wire [7:0] config_data = {4'b0000, div_automap, sd_cd, pause_button, magic_button};
+wire [7:0] config_data = {4'b0000, div_automap, 1'b1, pause_button, magic_button};
 always @(posedge clk28 or negedge rst_n) begin
     if (!rst_n)
         config_rd <= 0;
diff --git a/fpga/rtl/top.sv b/fpga/rtl/top.sv
index eec4756..0c2bc4a 100755
--- a/fpga/rtl/top.sv
+++ b/fpga/rtl/top.sv
@@ -234,7 +234,8 @@ wire magic_dout_active;
 wire magic_mode, magic_map;
 wire joy_sinclair, up_en, ay_en, covox_en, soundrive_en;
 panning_t panning;
-divmmc_t divmmc_en;
+wire divmmc_en, zc_en;
+
 magic magic0(
     .rst_n(n_rstcpu),
     .clk28(clk28),
@@ -249,7 +250,6 @@ magic magic0(
 
     .magic_button(ps2_key_magic),
     .pause_button(ps2_key_pause),
-    .sd_cd(sd_cd),
     .div_automap(div_automap),
 
     .magic_mode(magic_mode),
@@ -262,6 +262,7 @@ magic magic0(
     .joy_sinclair(joy_sinclair),
     .panning(panning),
     .divmmc_en(divmmc_en),
+    .zc_en(zc_en),
     .ulaplus_en(up_en),
     .ay_en(ay_en),
     .covox_en(covox_en),
@@ -387,13 +388,15 @@ divmmc divmmc0(
     .clk28(clk28),
     .ck14(ck14),
     .ck7(ck7),
-    .en(divmmc_en == DIVMMC_ON || divmmc_en == DIVMMC_NOOS),
-    .en_hooks(divmmc_en == DIVMMC_ON),
+    .en(divmmc_en),
+    .en_hooks(divmmc_en),
+    .en_zc(zc_en),
 
     .bus(bus),
     .d_out(div_dout),
     .d_out_active(div_dout_active),
 
+    .sd_cd(sd_cd),
     .sd_miso(sd_miso_tape_in),
     .sd_mosi(sd_mosi0),
     .sd_sck(sd_sck),
@@ -410,7 +413,7 @@ divmmc divmmc0(
     .ramwr_mask(div_ramwr_mask),
     .cpuwait(div_wait)
 );
-assign sd_mosi_tape_out = (divmmc_en == DIVMMC_OFF)? tape_out : sd_mosi0;
+assign sd_mosi_tape_out = (!divmmc_en && !zc_en)? tape_out : sd_mosi0;
 
 
 /* ULAPLUS */
@@ -498,7 +501,7 @@ memcontrol memcontrol0(
     .port_1ffd(port_1ffd),
     .port_dffd(port_dffd),
     .rampage_ext(rampage_ext),
-    .divmmc_en(divmmc_en != DIVMMC_OFF),
+    .divmmc_en(divmmc_en),
     .div_ram(div_ram),
     .div_map(div_map),
     .div_ramwr_mask(div_ramwr_mask),
diff --git a/rom/Makefile b/rom/Makefile
index 20dc345..b3e382d 100644
--- a/rom/Makefile
+++ b/rom/Makefile
@@ -3,9 +3,9 @@ bank00=128-0.rom              # 0x00000
 bank01=128-1.rom              # 0x04000
 bank02=../rom_src/main.bin    # 0x08000
 bank03=ESXMMC.BIN ESXMMC.BIN  # 0x0C000
-bank04=dvmen3e0.rom           # 0x10000
-bank05=dvmen3e1.rom           # 0x14000
-bank06=dvmen3e2.rom           # 0x18000
+bank04=zcen3e0.rom            # 0x10000
+bank05=zcen3e1.rom            # 0x14000
+bank06=zcen3e2.rom            # 0x18000
 bank07=zero8k.bin zero8k.bin  # 0x1C000
 
 sizif.rom: ${bank00} ${bank01} ${bank02} ${bank03} ${bank04} ${bank05} ${bank06} ${bank07}
diff --git a/rom/dvmen3e0.rom b/rom/zcen3e0.rom
similarity index 100%
rename from rom/dvmen3e0.rom
rename to rom/zcen3e0.rom
diff --git a/rom/dvmen3e1.rom b/rom/zcen3e1.rom
similarity index 90%
rename from rom/dvmen3e1.rom
rename to rom/zcen3e1.rom
index d988f24e1a8113ea5254b3964a1efc64b1d505ec..2642148ea89e26aca95ad103c547f561a3e7846e 100644
GIT binary patch
delta 401
zcmbV@ze@sP9LDc^r*B!2MIoXD_iis8WL%}DuV-Ot5giRWgp)%MNEB^S(JhTl@8nQZ
z&=eL&L|YBv54yi08nSB;`U}2x^(XW!AD$1-V_9HXa9dF1kYTSY7gG?kKh?cSxUx$N
z85tTvB)%YIpCl8YICmNGuxN&@4BoIX-gjQP)0!T}$Bs^Zo0v)!U{~y<Do_>8RMpIJ
zwt)&=<7@?e^q8{@`so>GaSYOP&SE%51!oLZTIY-+Qj@a?_Gyu`iS9Sf(o4>UaEV@X
zrqFF+rSnh`&GeC-<NI*h(EV;S(tX1%we-hjb@Pu!bu}8n88r)%)XN3kUT)ka#F4Ti
z06=QqZCsY9`Q#Y_$pOdIocd@#RV(YnHHvzz>}=?sY<rV7o$rxAT-IJb=$x@eq(J`t
i;8}}H+ToTq=C;8%Ao~Xu5<sbiib2}_|Hrlr3w{7tEVl^&

delta 350
zcmZo@U~Fh$+~Cg4l+V1`lX<QzqxR<K3b`VTOE-s_+A=Y2m^|71C8PM}S_^YVW<|dP
zleb&?Ni^F2TdN`QZ|kYEHfK+0asS(S%7_ibn=EVP&X_ql)hdxOXYz5YY(Ezp4ex)<
zik>zaF8^2*Yi%@a|FJ5z*=U&k<5%pn(a`@Vpg6@wL*t)<;w&2t#ee@4{cSX){{2@B
zwb2lM_Tis_;(Qwou73`SD{M5F6{99MSi3PMO+Id2&8V>1$tIt1@<V%($sg=l2Oa)z
LC%k!*T^=I<sKt%{

diff --git a/rom/dvmen3e2.rom b/rom/zcen3e2.rom
similarity index 96%
rename from rom/dvmen3e2.rom
rename to rom/zcen3e2.rom
index 5a6aa754089d3ccd4d301303d0fa3d58e1167323..57fc1ada208dff93b495af57f69baa4eb6e399c3 100644
GIT binary patch
delta 250
zcmZo@U~Fh$+)$#*7(TgFRbC=oM%Gz__3b7R38uH3L=}EV*|8s%X5tH<yhb(Ilu?7p
zj_Gpw?eLE$)fn^`LSv7z{g+@o>VNit+F4$;%FE$3441=efw&5YtAV%zh$p+KsSAd`
zU8L~Gyz1gX39qA!Mhv&ZC)cQ%`h+vQ-2_AjZ-+Agh0M>gt9?Dn#&tVf;LpL2C;7tP
zR!CQER`@RQz%Jsff|`Mq-M`D>M;XHzp5A@>@a<-Xx0|2defZGs|7D<Vpf!Kha{0p3
nf#&1`@iYE#pdA(J8NA_((jh|eK;g}A)sqAm!#4+5Y+wffkjZJB

delta 250
zcmZo@U~Fh$+)$#*_<C}ws=UN&8Choy*0-BPB$(cA5>@yeWygM4nu+iA<Ta|vrvEgU
z?EYSUe*5*ulWGil456_{+5Sr~9`!$aK<zBATIJ=}H4K+u*8*`B5LW|n1rSemQBxOu
z{dSSUAM>h<2PM3YG8!@5em%KH&D7^L!`n?jbny0T2B47nS$4IrN7=Y;zZUp&@Z(9o
z*KaGNt2Qfqmv~?oaaKXiz{>95<=00UUo$+t`}E=4%?xihKfU|#q22$>K;1xV{;K8j
py-o+3lMlqt_``vARH$e0zFw3L5sC*2Z+@$uB*6H3bAZJLb^xK=eOv$l

diff --git a/rom/dvmen3e3.rom b/rom/zcen3e3.rom
similarity index 93%
rename from rom/dvmen3e3.rom
rename to rom/zcen3e3.rom
index e83937de5961d412171e901d33091bda6bf72847..01b5b5ff61c3e306fac5d89a3b981540d232e904 100644
GIT binary patch
delta 941
zcmZWn&r92282-NWSDe$DRj{&yNgSi37fnTL8pFKkNfZ@5L<9$;mw_;0F3!>5V1K~&
zAMDbTR1gn?A+1Gc#sYSuhv9lClJN=q4n=wzrh6M~=hz2<H(%c8&GS6(W184B@!sQr
z&pt@*KMBkwGHji#mz|0up}Zq8c}JL96j5H7oD-S6)`PDz)PPS}ZfcRv^PSL<<tFFo
zd@P{4QT~FhLR+;7K+sK%rA?I@tD6(lID8iC+Ne~kr5amf&)oq_<EXKr^-)6!kY!dz
zgc@5e&hS5)cLLHmRKUnj_v|k!U6w;cYsg5~bUH2Qs@TwTayL;B@d*8Xex>z!RZi|A
zN{G;D1?e(N1XSRV?u}{n+V9jB3;Wl29iDV;-Ck3nm}RHgnHL{;IUdh~xcC~}eGRI!
z>d(+O*I<(@TRB90Z`99LHc@5p{`&TAdTXEmUi_>S->7z3IkR_Ft8weRRSq*pN}~}$
z!{ZU09D{)$k1od(3D$DT#}x<6)-qtmklg0qO{7k;eZb!V!ql(_Qqf9W>?BeLSsD~O
z+LE`%z{X0oP^wxQu)Bc^$ZXlBtmrZ(N;;#<451r7A}pl1QxhYG?iEkX;ZLUKm(x1F
z9-xL6l2@RD)oMH7FMcgHc1G#o=nP#|x`~TpDVK@Ga45*3UICrh_wbc~dXtab{@8<H
z(7uava)78{y?{|v3O3uyR1Xu0BhgH_`SuV!U0e~vMC1qnMsX<%1L!>bv$<^`q4}v%
zyiC!TKEk0By3j#Dw6{K>+)TlUYH8T+QNg=x+dLtzI_o#uUqK*>QmSps1zl2D;$|8#
z24r}dzyx$E3<2G(I9ymch!veFA3Ha5oKhqL#IyatRS1(IJmPHvthO`;2ta^54u266
ze@^uXp$q)E7$MQK`ti*urHi;z*n=1NP%Qx`TBuoC576-3|0gWBa`S)re!}+$z5uX?

delta 941
zcmZo@U~Fh$+>pe|eEXmL=2X@I<9ddH1p{rrFIBxi$!cFcqYYJ!B-OBi4p3^?|Np-*
fgQ2A`qlG!CzGq;dhW(`5iqPSPU{b<bWXlWy&{q%X

diff --git a/rom_src/config.asm b/rom_src/config.asm
index f1ca4f0..25dcfb0 100644
--- a/rom_src/config.asm
+++ b/rom_src/config.asm
@@ -28,7 +28,7 @@ _reserv2   DB 0
 _reserv3   DB 0
 joystick   DB 0
 ay         DB 1
-divmmc     DB 2
+sd         DB 2
 ulaplus    DB 1
 dac        DB 3
     ENDS
diff --git a/rom_src/main.asm b/rom_src/main.asm
index 0d870ba..24f8669 100644
--- a/rom_src/main.asm
+++ b/rom_src/main.asm
@@ -237,17 +237,16 @@ init_cpld:
 
 
 detect_sd_card:
-    ld a, #ff                   ; read sd_cd state in bit 2 of #FFFF port
-    in a, (#ff)                 ; ...
-    bit 2, a                    ; check sd_cd == 0 (card is insert)
+    in a, (#77)                 ; read sd_cd state from ZC status port
+    bit 0, a                    ; check sd_cd == 0 (card is insert)
     jr z, .is_insert            ; yes?
 .no_card:
-    xor a                       ; divmmc = OFF
-    ld (cfg_saved.divmmc), a    ; ...
+    xor a                       ; sd = OFF
+    ld (cfg_saved.sd), a        ; ...
     ret
 .is_insert:
-    ld a, 1                     ; divmmc = ON
-    ld (cfg_saved.divmmc), a    ; ...
+    ld a, 1                     ; sd = divmmc
+    ld (cfg_saved.sd), a        ; ...
     ret
 
 
diff --git a/rom_src/menu_structure.asm b/rom_src/menu_structure.asm
index f8c224e..7abb1c0 100644
--- a/rom_src/menu_structure.asm
+++ b/rom_src/menu_structure.asm
@@ -34,7 +34,7 @@ menudefault: MENU_DEF 20
     MENUENTRY_T str_machine     menu_machine_value_cb     menu_machine_cb
     MENUENTRY_T str_panning     menu_panning_value_cb     menu_panning_cb
     MENUENTRY_T str_joystick    menu_joystick_value_cb    menu_joystick_cb
-    MENUENTRY_T str_divmmc      menu_divmmc_value_cb      menu_divmmc_cb
+    MENUENTRY_T str_sd          menu_sd_value_cb          menu_sd_cb
     MENUENTRY_T str_ulaplus     menu_ulaplus_value_cb     menu_ulaplus_cb
     MENUENTRY_T str_dac         menu_dac_value_cb         menu_dac_cb
     MENUENTRY_T str_exit        menu_exit_value_cb        menu_exit_cb
@@ -81,14 +81,14 @@ menu_joystick_value_cb:
     DW str_joystick_kempston_end-2
     DW str_joystick_sinclair_end-2
 
-menu_divmmc_value_cb:
+menu_sd_value_cb:
     ld ix, .values_table
-    ld a, (cfg.divmmc)
+    ld a, (cfg.sd)
     jp menu_value_get
 .values_table:
     DW str_off_end-2
-    DW str_on_end-2
-    DW str_divmmc_noos_end-2
+    DW str_divmmc_end-2
+    DW str_zc3e_end-2
 
 menu_ulaplus_value_cb:
     ld ix, .values_table
@@ -163,11 +163,11 @@ menu_joystick_cb:
     out (c), a
     ret
 
-menu_divmmc_cb:
-    ld a, (cfg.divmmc)
+menu_sd_cb:
+    ld a, (cfg.sd)
     ld c, 2
     call menu_handle_press
-    ld (cfg.divmmc), a
+    ld (cfg.sd), a
     ld bc, #09ff
     out (c), a
     ret
diff --git a/rom_src/strings.asm b/rom_src/strings.asm
index b81d38a..8ed729c 100644
--- a/rom_src/strings.asm
+++ b/rom_src/strings.asm
@@ -75,11 +75,14 @@ str_joystick_kempston_end:
 str_joystick_sinclair: DB "Sinclair",0
 str_joystick_sinclair_end:
 
+str_sd: DB "SD card",0
+str_sd_end:
+
 str_divmmc: DB "DivMMC",0
 str_divmmc_end:
 
-str_divmmc_noos: DB "NO OS",0
-str_divmmc_noos_end:
+str_zc3e: DB "ZC/+3e",0
+str_zc3e_end:
 
 str_ulaplus: DB "ULA+",0
 str_ulaplus_end