Merge pull request #2 from ryucats/master

Fix ROM access logic

README.md

@@ -24,8 +24,8 @@ with what made the layout easier.
 
 ## Parts List
 
-* A 74HCT245 octal bus transceiver (U1)
-* A 28C256 EEPROM (U2)
+* A 74LS245 octal bus transceiver (non-TTL appears to have issues with the ROM address decode logic) (U1)
+* A 28C256 EEPROM (28-pin JEDEC EPROMs such as the 27128 also work) (U2)
 * A 1.8432 MHz 5V oscillator (U3)
 * A 22V10 GAL (any speed or variety should work) (U4)
 * A W65C51N ACIA (U5)

gal/ssc-cr-2023030903.jed

@@ -0,0 +1,60 @@
+
+CUPL(WM)        5.0a  Serial# 60008009
+Device          g22v10  Library DLIB-h-40-1
+Created         Fri Mar 10 06:33:40 2023
+Name            Simple Serial Card
+Partno          SSC0001
+Revision        01
+Date            3/9/23
+Designer        Chris RYU
+Company         RyuCats
+Assembly        None
+Location        None
+*QP24 
+*QF5892 
+*G0 
+*F0 
+*L00896 00000000000000000000000000001111
+*L00928 11111111111111111111111111111111
+*L00960 11111111111111111111101111111111
+*L00992 11111111111111111111000000000000
+*L01472 00000000000000000000000011111111
+*L01504 11111111111111111111111111111111
+*L01536 11111111111111111111011111111111
+*L01568 11111111110111110000000000000000
+*L02144 00000000000011111111111111111111
+*L02176 11111111111111111111111111111111
+*L02208 11111111111111111111011111111111
+*L02240 11111111111111111111111111111011
+*L02272 11111111111111110000000000000000
+*L02880 00000000000000000000000011111111
+*L02912 11111111111111111111111111111111
+*L02944 11111111111111111111111111111111
+*L02976 11110111111111111111111111111111
+*L03008 11111111101111111111111111110000
+*L03648 00001111111111111111111111111111
+*L03680 11111111111111111111111111111111
+*L03712 11111111111111111111011111111111
+*L03744 11111111111111111111101111111111
+*L03776 11111111000000000000000000000000
+*L04288 00000000000000000000000011111111
+*L04320 11111111111111111111111111111111
+*L04352 11111111111111110111011111111111
+*L04384 11111111110111110000000000000000
+*L04864 00000000000000000000111111111111
+*L04896 11111111111111111111111111111111
+*L04928 11111111111111110111111111111111
+*L04960 11011111111110111111111111111111
+*L04992 11111111111111111111111111111111
+*L05024 10111111111111111111011101110111
+*L05056 11110000000000000000000000000000
+*L05344 00000000000000000000000011111111
+*L05376 11111111111111111111111111111111
+*L05408 11111111111111111111111111111111
+*L05440 11111101111111111111111101111111
+*L05472 11111111111111111111111111110000
+*L05792 00000000000000000000111111111111
+*L05824 11110101001101010011010000110011
+*L05856 00000011000000110000001100010000
+*C7DCD
+*9C8B

gal/ssc_gal_wincupl.pld

@@ -0,0 +1,61 @@
+Name            Simple Serial Card;
+Partno          SSC0001;
+Revision        01;
+Date            3/9/23;
+Designer        Chris RYU;
+Company         RyuCats;
+Location        None;
+Assembly        None;
+Device          g22v10;
+
+/* Inputs */
+
+Pin 1 = reset;
+Pin 2 = CTS;
+Pin 3 = io_C800;
+Pin 4 = slot_select;
+Pin 5 = io_slot_access;
+Pin 6 = RW;
+Pin 7 = A11;
+Pin 8 = A10;
+Pin 9 = A9;
+Pin 10 = A8;
+Pin 11 = A3;
+
+/* Outputs */
+
+Pin 14 = rom_c800_enable;
+Pin 15 = rom_latch;
+Pin 16 = ls245_enable;
+Pin 17 = eprom_a8;
+Pin 18 = eprom_a9;
+Pin 19 = eprom_a10;
+Pin 20 = rom_enable;
+Pin 21 = PHI2;
+
+
+/*  Latch (RS flip-flop) definition:
+    Q  = (Q & RESET) # !SET;
+*/
+
+PHI2 = !slot_select; /* per schematic */
+
+cf00_access = io_C800 # !(A8 & A9 & A10); /* CF00 access, pull low */
+
+/* 
+    if either reset or cf00 access is pulled low, then rom_latch = 1
+    if io_slot_access is 0, then rom_latch = 0
+    if io_slot_access is 1, then rom_latch = no change
+*/
+
+/* Q = ROM_LATCH RESET = io_slot_access SET = (reset & cf00_access) */
+rom_latch = (rom_latch & io_slot_access) # !(reset & cf00_access);
+
+rom_c800_enable = rom_latch # io_C800; /* enable if both pulled low */
+
+ls245_enable = ( io_slot_access & rom_c800_enable & slot_select); /* c800 ? */
+rom_enable = (io_slot_access & rom_c800_enable);
+
+eprom_a8 = A8 # !A11;
+eprom_a9 = A9 # !A11;
+eprom_a10 = A10 # !A11;

rom/Makefile

@@ -0,0 +1,16 @@
+# Simple makefile to snarf the Apple SuperSerialCard ROM image and patch it
+# for ADTPro bootstrapping
+
+ROM_SOURCE = https://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Interface%20Cards/Serial/Apple%20II%20Super%20Serial%20Card/ROM%20Images/Apple%20II%20Super%20Serial%20Card%20ROM%20-%20341-0065-A.bin
+
+all: 341-0065.bin adtpro-patch-341-0065.bin
+
+adtpro-patch-341-0065.bin: adtpro-patch-341-0065.xdelta
+	xdelta3 -d -s 341-0065.bin adtpro-patch-341-0065.xdelta \
+		adtpro-patch-341-0065.bin
+
+341-0065.bin:
+	curl -o 341-0065.bin $(ROM_SOURCE)
+
+clean:
+	rm -f 341-0065.bin adtpro-patch-341-0065.bin