Improve assembler controls

7 files changed, 133 insertions, 58 deletions

diff --git a/Makefile b/Makefile
index 6c79d9b..ba0f8a3 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,8 @@
+.PHONY: assembler
+assembler: hexedit
+	sleep 1
+	$(MAKE) -C assembler serial
+
 .PHONY: hexedit
 hexedit: octedit
 	sleep 1
@@ -6,3 +11,8 @@ hexedit: octedit
 .PHONY: octedit
 octedit:
 	$(MAKE) -C octedit flash
+
+.PHONY: serial
+serial:
+	$(MAKE) -C hexedit serial
+	$(MAKE) -C assembler serial
diff --git a/assembler/Makefile b/assembler/Makefile
index 0225069..45988ba 100644
--- a/assembler/Makefile
+++ b/assembler/Makefile
@@ -1,29 +1,38 @@
-PICO = /dev/disk/by-label/RPI-RP2
+DEVICE = /dev/ttyUSB0
 
-assemble.uf2: assemble.elf
-	../elf/elf2uf2 assemble.elf assemble.uf2
+.PHONY: build
+build: assemble.he
+
+assemble.he: assemble.bin
+	od -An -tx2 -v assemble.bin | sed "s/^ //" | tr " " "\n" | tr [:lower:] [:upper:] | sed "s/^/0x/" > assemble.he
+
+assemble.bin: assemble.elf
+	arm-none-eabi-objcopy -O binary assemble.elf assemble.bin
 
 objects = main.o uart.o assemble.o register.o octal.o opcode.o
 
-assemble.elf: $(objects)
-	arm-none-eabi-ld -T pico_ram_only.ld -o assemble.elf $(objects) ../setup/setup.so
+assemble.elf: pico_bin.ld $(objects)
+	arm-none-eabi-ld -T pico_bin.ld -o assemble.elf $(objects)
 
 $(objects): %.o: %.s
 	arm-none-eabi-as -o $@ $<
 
 .PHONY: clean
 clean:
-	rm assemble.elf assemble.uf2 *.o
-
-.PHONY: flash
-flash: $(PICO) assemble.uf2
-	cat assemble.uf2 > $(PICO)
-
-.PHONY: check
-check: $(PICO)
-	@echo Ready to flash
-
-$(PICO):
-	@echo "RPI-RP2 bootloader drive not found"
-	@echo Connect the pico with USB cable while holding bootsel button
+	rm assemble.elf assemble.bin assemble.he *.o slowcat
+
+.PHONY: dump
+dump: assemble.bin
+	@od -Ax -tx2 -v assemble.bin
+
+.PHONY: serial
+serial: $(DEVICE) assemble.he slowcat
+	cat assemble.he | tr "\n" "\r" | ./slowcat | picocom -b 115200 -q $(DEVICE)
+	@echo
+	echo -n "G" | picocom -b 115200 -q $(DEVICE)
+	@echo
+
+$(DEVICE):
+	@echo Serial device not found
+	@echo Connect USB cable from USB-UART bridge
 	@false
diff --git a/assembler/assemble.s b/assembler/assemble.s
index 9f5c022..704b7cf 100644
--- a/assembler/assemble.s
+++ b/assembler/assemble.s
@@ -9,7 +9,6 @@
 // - make subroutine addresses explicit
 // - test each instruction
 // - decide on additional push or pops
-// - add GO to get_char
 
 assemble:   PUSH    {LR}
             LDR     R0, =uart_send
@@ -72,4 +71,5 @@ done_stuff: MOV     R0, R8          // copy the end_char into R0
             BLX     R9              // echo the space (or carriage return)
 here:       LSRS    R7, 0x8         // get next parse instruction
             BNE     main_loop       // if it's nonzero there are more things to parse
+            MOVS    R0, 0
             POP     {PC}
diff --git a/assembler/main.s b/assembler/main.s
index 1795823..a9fd109 100644
--- a/assembler/main.s
+++ b/assembler/main.s
@@ -5,22 +5,31 @@
 .type main, %function
 .global main
 
-main:
-  bl start_xosc
-  bl setup_clocks
-  bl setup_gpio
-  bl setup_uart
-  b assembler
-
-assembler:  LDR     R0, =0x20001000         // SRAM_BASE
-            MOV     R11, R0
+main:       LDR     R0, =0x20000000         // SRAM_BASE
+0:          MOV     R11, R0
             ADDS    R1, R0, 1               // JUMP ADDRESS
             MOV     R12, R1
 1:          BL      PROMPT                  // SHOW PROMPT
             BL      assemble
-            B       2f                      // TODO condition
+            CMP     R0, 1                   // SET NEW ADDRESS
+            BNE     2f
+            MOVS    R0, '\r                 // SEND CR
+            BL      uart_send
+            MOV     R1, R11                 // GET ADDRESS
+            LSRS    R1, 16                  // SHIFT OUT LOWER HALFWORD
+            MOVS    R0, R1                  // SAVE IN R0
+            LSLS    R1, 16                  // SHIFT BACK
+            MOV     R11, R1                 // SAVE ALTERRED ADDRESS
+            MOVS    R1, 4                   // SEND HEX WITH WIDTH 4
+            BL      send_hex
+            BL      get_hex                 // GET HEX INPUT FOR OFFSET
+            MOV     R0, R11                 // ADD OFFSET TO ADDRESS
+            ADDS    R0, R4
+            B       0b
+2:          CMP     R0, 2                   // JUMP TO NEW CODE
+            BNE     3f
             BX      R12
-2:          MOV     R7, R11                 // STORE INSTRUCTION WORD
+3:          MOV     R7, R11                 // STORE INSTRUCTION WORD
             STRH    R6, [R7]
             MOVS    R0, '\r                 // NEW LINE
             BL      uart_send
@@ -35,11 +44,13 @@ assembler:  LDR     R0, =0x20001000         // SRAM_BASE
 
 PROMPT:     PUSH    {LR}
             MOV     R0, R11                 // CURRENT ADDRESS
+            MOVS    R1, 8
             BL      send_hex
             MOVS    R0, '                   // SPACE
             BL      uart_send
             MOV     R1, R11                 // CURRENT CONTENTS
             LDRH    R0, [R1]
+            MOVS    R1, 4
             BL      send_hex
             MOVS    R0, '                   // SPACE
             BL      uart_send
diff --git a/assembler/pico_ram_only.ld b/assembler/pico_bin.ld
index eb2450e..3059501 100644
--- a/assembler/pico_ram_only.ld
+++ b/assembler/pico_bin.ld
@@ -2,12 +2,12 @@ ENTRY(main)
 
 MEMORY {
   FLASH(rx) : ORIGIN = 0x10000000, LENGTH = 2M
-  SRAM(rwx) : ORIGIN = 0x20000000, LENGTH = 264K
+  SRAM(rwx) : ORIGIN = 0x20001000, LENGTH = 260K
 }
 
 SECTIONS {
   .text : {
-    *(.text)
+    *(.text);
     . = ALIGN(4);
   } > SRAM
 }
diff --git a/assembler/slowcat.c b/assembler/slowcat.c
new file mode 100644
index 0000000..99493ae
--- /dev/null
+++ b/assembler/slowcat.c
@@ -0,0 +1,11 @@
+#include <unistd.h>
+#include <stdint.h>
+
+int main() {
+  uint8_t byte;
+  while (read(STDIN_FILENO, &byte, 1)) {
+    write(STDOUT_FILENO, &byte, 1);
+    usleep(1000);
+  }
+  return 0;
+}
diff --git a/assembler/uart.s b/assembler/uart.s
index e1f5e8b..5712268 100644
--- a/assembler/uart.s
+++ b/assembler/uart.s
@@ -10,11 +10,13 @@
 .type uart_recv, %function
 .type get_char, %function
 .type send_hex, %function
+.type get_hex, %function
 
 .global uart_send
 .global uart_recv
 .global get_char
 .global send_hex
+.global get_hex
 
 uart_send:  LDR     R1, =UART0_BASE         // 0x0000 0x4917
             MOVS    R3, 0b1 << 5            // 0x0002 0x2320  ; TX FIFO FULL
@@ -33,30 +35,62 @@ uart_recv:  LDR     R1, =UART0_BASE         // 0x000E 0x4914
 get_char:   PUSH    {LR}                    // 0x001C 0xB500
             BL      uart_recv               // 0x001E 0xF7FF
                                             // 0x0020 0xFFF6
-            CMP     R0, R8                  // 0x0022 0x4540
+            CMP     R0, '<
+            BNE     1f
+            MOVS    R0, 1
+            B       2f
+1:          CMP     R0, '>
+            BNE     3f
+            MOVS    R0, 2
+2:          POP     {R1}
+            POP     {R1}
+3:          CMP     R0, R8                  // 0x0022 0x4540
             POP     {PC}                    // 0x0024 0xBD00
-send_hex:   PUSH    {LR}                    // 0x0026 0xB500
-            LSLS    R4, R0, 16              // 0x0028 0x
-            MOVS    R0, '0                  // 0x002A 0x2030
-            BL      uart_send               // 0x002C 0xF7FF
-                                            // 0x002E 0xFFE8
-            MOVS    R0, 'x                  // 0x0030 0x2078
-            BL      uart_send               // 0x0032 0xF7FF
-                                            // 0x0034 0xFFE5
-            MOVS    R5, 4                   // 0x0036 0x2504 ; FOUR NIBBLES TO PRINT
-0:          MOVS    R0, 28                  // 0x0038 0x201C ; ROTATE LEFT 4
-            RORS    R4, R0                  // 0x003A 0x41C4
-            MOVS    R0, 0xF                 // 0x003C 0x200F ; LOWEST NIBBLE MASK
-            ANDS    R0, R4                  // 0x003E 0x4020
-            CMP     R0, 0x9                 // 0x0040 0x0000 ; NUMBER OR LETTER?
-            BHI     1f                      // 0x0042 0xD801
-            ADDS    R0, '0                  // 0x0044 0x3030
-            B       2f                      // 0x0046 0xE000
-1:          ADDS    R0, ('A - 0xA)          // 0x0048 0x3037
-2:          BL      uart_send               // 0x004A 0xF7FF
-                                            // 0x004C 0xFFD9
-            SUBS    R5, 1                   // 0x004E 0x3D01
-            BNE     0b                      // 0x0050 0xD1F2
-            POP     {PC}                    // 0x0052 0xBD00
-                                            // 0x0054 0x4000 ; UART0_BASE
-                                            // 0x0056 0x4003
+send_hex:   PUSH    {LR}          // 000350 132400 B500
+            MOVS    R4, R0        // 000352 000004 0004
+            MOVS    R5, R1        // 000354 000015 000D
+            LSLS    R1, 0x2       // 000356 000211 0049
+            RORS    R4, R1        // 000360 040714 41CC
+            MOVS    R0, 0x30      // 000362 020060 2030 ASCII 0
+            BL      uart_send     // 000364 043710  UARTTX
+            MOVS    R0, 0x78      // 000366 020170  ASCII x
+            BL      uart_send     // 000370 043710  UARTTX
+0:          MOVS    R0, 0x1C      // 000372 020034
+            RORS    R4, R0        // 000374 040704
+            MOVS    R0, 0x0F      // 000376 020017
+            ANDS    R0, R4        // 000400 040040
+            CMP     R0, 0x9       // 000402 024011
+            BHI     1f            // 000404 154001
+            ADDS    R0, 0x30      // 000406 030060  ASCII 0
+            B       2f            // 000410 160000
+1:          ADDS    R0, 0x37      // 000412 030067  ASCII A MINUS 10
+2:          BL      uart_send     // 000414 043710  UARTTX
+            SUBS    R5, 1         // 000416 036401
+            BNE     0b            // 000420 150763
+            POP     {PC}          // 000422 136400
+get_hex:    PUSH    {LR}          // 000224 132400
+            MOVS    R4, 0x0       // 000226 022000
+            MOVS    R5, 0x4       // 000230 022404
+10:         BL      uart_recv     // 000232 043700  HEX LOOP, UARTRX
+            CMP     R0, 0x30      // 000234 024060  ASCII 0
+            BLO     10b           // 000236 151774
+            CMP     R0, 0x39      // 000240 024071  ASCII 9
+            BLS     20f           // 000242 154406
+            CMP     R0, 0x41      // 000244 024101  ASCII A
+            BLO     10b           // 000246 151770
+            CMP     R0, 0x46      // 000250 024106  ASCII F
+            BHI     10b           // 000252 154366
+            BL      uart_send     // 000254 043710  UARTTX
+            SUBS    R0, 0x37      // 000256 034067  ASCII A MINUS 10
+            B       30f           // 000260 160001
+20:         BL      uart_send     // 000262 043710  UARTTX
+            SUBS    R0, 0x30      // 000264 034060  ASCII 0
+30:         LSLS    R4, 0x4       // 000266 000444
+            ADDS    R4, R0        // 000270 014044
+            SUBS    R5, 0x1       // 000272 036401
+            BNE     10b           // 000274 150755
+40:         BL      uart_recv     // 000276 043700  UARTRX
+            CMP     R0, '\r       // 000300 024015  CARRIAGE RETURN
+            BNE     40b           // 000302 150774
+            BL      uart_send     // 000304 043710  UARTTX
+            POP     {PC}          // 000306 136400