diff options
Diffstat (limited to 'assembler')
| -rw-r--r-- | assembler/main.s | 20 | ||||
| -rw-r--r-- | assembler/uart.s | 74 |
2 files changed, 47 insertions, 47 deletions
diff --git a/assembler/main.s b/assembler/main.s index a9fd109..983437d 100644 --- a/assembler/main.s +++ b/assembler/main.s @@ -16,13 +16,15 @@ main: LDR R0, =0x20000000 // SRAM_BASE MOVS R0, '\r // SEND CR BL uart_send MOV R1, R11 // GET ADDRESS - LSRS R1, 16 // SHIFT OUT LOWER HALFWORD + LSRS R1, 12 // SHIFT OUT LOWER 12 BITS MOVS R0, R1 // SAVE IN R0 - LSLS R1, 16 // SHIFT BACK + LSLS R1, 12 // 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 + MOVS R1, 20 // SEND OCTAL WITH WIDTH 20 + BL send_oct + BL get_oct // GET OCTAL INPUT FOR OFFSET + MOVS R0, 0x1 + BICS R4, R0 MOV R0, R11 // ADD OFFSET TO ADDRESS ADDS R0, R4 B 0b @@ -44,14 +46,14 @@ main: LDR R0, =0x20000000 // SRAM_BASE PROMPT: PUSH {LR} MOV R0, R11 // CURRENT ADDRESS - MOVS R1, 8 - BL send_hex + MOVS R1, 32 + BL send_oct MOVS R0, ' // SPACE BL uart_send MOV R1, R11 // CURRENT CONTENTS LDRH R0, [R1] - MOVS R1, 4 - BL send_hex + MOVS R1, 16 + BL send_oct MOVS R0, ' // SPACE BL uart_send POP {PC} // RETURN diff --git a/assembler/uart.s b/assembler/uart.s index 5712268..203c3af 100644 --- a/assembler/uart.s +++ b/assembler/uart.s @@ -9,14 +9,14 @@ .type uart_send, %function .type uart_recv, %function .type get_char, %function -.type send_hex, %function -.type get_hex, %function +.type send_oct, %function +.type get_oct, %function .global uart_send .global uart_recv .global get_char -.global send_hex -.global get_hex +.global send_oct +.global get_oct uart_send: LDR R1, =UART0_BASE // 0x0000 0x4917 MOVS R3, 0b1 << 5 // 0x0002 0x2320 ; TX FIFO FULL @@ -46,46 +46,44 @@ get_char: PUSH {LR} // 0x001C 0xB500 POP {R1} 3: CMP R0, R8 // 0x0022 0x4540 POP {PC} // 0x0024 0xBD00 -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 +send_oct: PUSH {LR} + MOVS R4, R0 + MOVS R0, R1 + MOVS R1, 32 + SUBS R1, R0 + LSLS R4, R1 + MOVS R5, 0 +loop1: CMP R0, 3 + BLO done + SUBS R0, 3 + ADDS R5, 1 + B loop1 +done: TST R0, R0 + BEQ loop2 + RSBS R0, 0 + ADDS R0, 32 + RORS R4, R0 + ADDS R5, 1 +loop2: MOVS R0, 0x07 + ANDS R0, R4 + ADDS R0, 0x30 + BL uart_send + MOVS R0, 0x1D + RORS R4, R0 + SUBS R5, 1 + BNE loop2 + POP {PC} +get_oct: 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 + CMP R0, 0x37 // 000240 024071 ASCII 7 + BHI 10b // 000242 154406 + BL uart_send // 000262 043710 UARTTX SUBS R0, 0x30 // 000264 034060 ASCII 0 -30: LSLS R4, 0x4 // 000266 000444 +30: LSLS R4, 0x3 // 000266 000444 ADDS R4, R0 // 000270 014044 SUBS R5, 0x1 // 000272 036401 BNE 10b // 000274 150755 |