Test units are now in their own folder 'z80_test', add programmer cli interface

1 files changed, 441 insertions, 0 deletions

diff --git a/sw/z80_tests/usart/build/usart.lst b/sw/z80_tests/usart/build/usart.lst
new file mode 100644
index 0000000..7706cff
--- /dev/null
+++ b/sw/z80_tests/usart/build/usart.lst
@@ -0,0 +1,441 @@
+                              1 ;--------------------------------------------------------
+                              2 ; File Created by SDCC : free open source ANSI-C Compiler
+                              3 ; Version 3.6.0 #9615 (Linux)
+                              4 ;--------------------------------------------------------
+                              5 	.module usart
+                              6 	.optsdcc -mz80
+                              7 	
+                              8 ;--------------------------------------------------------
+                              9 ; Public variables in this module
+                             10 ;--------------------------------------------------------
+                             11 	.globl _usart_word_length
+                             12 	.globl _usart_set_baudrate
+                             13 	.globl _usart_set_parity
+                             14 	.globl _usart_set_stop_bits
+                             15 	.globl _usart_set_autoflow
+                             16 	.globl _usart_init
+                             17 	.globl _usart_transmit
+                             18 	.globl _usart_receive
+                             19 	.globl _usart_write
+                             20 	.globl _usart_read
+                             21 ;--------------------------------------------------------
+                             22 ; special function registers
+                             23 ;--------------------------------------------------------
+                             24 ;--------------------------------------------------------
+                             25 ; ram data
+                             26 ;--------------------------------------------------------
+                             27 	.area _DATA
+                             28 ;--------------------------------------------------------
+                             29 ; ram data
+                             30 ;--------------------------------------------------------
+                             31 	.area _INITIALIZED
+   0000                      32 __usart:
+   0000                      33 	.ds 2
+                             34 ;--------------------------------------------------------
+                             35 ; absolute external ram data
+                             36 ;--------------------------------------------------------
+                             37 	.area _DABS (ABS)
+                             38 ;--------------------------------------------------------
+                             39 ; global & static initialisations
+                             40 ;--------------------------------------------------------
+                             41 	.area _HOME
+                             42 	.area _GSINIT
+                             43 	.area _GSFINAL
+                             44 	.area _GSINIT
+                             45 ;--------------------------------------------------------
+                             46 ; Home
+                             47 ;--------------------------------------------------------
+                             48 	.area _HOME
+                             49 	.area _HOME
+                             50 ;--------------------------------------------------------
+                             51 ; code
+                             52 ;--------------------------------------------------------
+                             53 	.area _CODE
+                             54 ;usart.c:5: void usart_set_baudrate(uint16_t baudrate)
+                             55 ;	---------------------------------
+                             56 ; Function usart_set_baudrate
+                             57 ; ---------------------------------
+   0000                      58 _usart_set_baudrate::
+   0000 DD E5         [15]   59 	push	ix
+   0002 DD 21 00 00   [14]   60 	ld	ix,#0
+   0006 DD 39         [15]   61 	add	ix,sp
+                             62 ;usart.c:8: _usart->LCR.divisor_latch_access = 1;
+   0008 2Ar00r00      [16]   63 	ld	hl,(__usart)
+   000B 01 04 00      [10]   64 	ld	bc,#0x0004
+   000E 09            [11]   65 	add	hl,bc
+   000F 7E            [ 7]   66 	ld	a,(hl)
+   0010 F6 80         [ 7]   67 	or	a,#0x80
+   0012 77            [ 7]   68 	ld	(hl),a
+                             69 ;usart.c:9: _usart->buffer = 0x00FF & baudrate; // LSBs
+   0013 2Ar00r00      [16]   70 	ld	hl,(__usart)
+   0016 DD 4E 04      [19]   71 	ld	c,4 (ix)
+   0019 71            [ 7]   72 	ld	(hl),c
+                             73 ;usart.c:10: memcpy(&_usart->IER, &(baudrate >>8), 1);
+   001A ED 5Br00r00   [20]   74 	ld	de,(__usart)
+   001E 13            [ 6]   75 	inc	de
+   001F DD 6E 05      [19]   76 	ld	l,5 (ix)
+   0022 26 00         [ 7]   77 	ld	h,#0x00
+   0024 7E            [ 7]   78 	ld	a, (hl)
+   0025 12            [ 7]   79 	ld	(de), a
+                             80 ;usart.c:12: _usart->LCR.divisor_latch_access = 0;
+   0026 2Ar00r00      [16]   81 	ld	hl,(__usart)
+   0029 01 04 00      [10]   82 	ld	bc,#0x0004
+   002C 09            [11]   83 	add	hl,bc
+   002D 7E            [ 7]   84 	ld	a,(hl)
+   002E E6 7F         [ 7]   85 	and	a,#0x7f
+   0030 77            [ 7]   86 	ld	(hl),a
+   0031 DD E1         [14]   87 	pop	ix
+   0033 C9            [10]   88 	ret
+                             89 ;usart.c:15: void usart_set_parity(int mode)
+                             90 ;	---------------------------------
+                             91 ; Function usart_set_parity
+                             92 ; ---------------------------------
+   0034                      93 _usart_set_parity::
+                             94 ;usart.c:18: _usart->LCR.even_parity = 1;
+   0034 2Ar00r00      [16]   95 	ld	hl,(__usart)
+   0037 01 04 00      [10]   96 	ld	bc,#0x0004
+   003A 09            [11]   97 	add	hl,bc
+                             98 ;usart.c:17: if (mode == USART_PARITY_EVEN) {
+   003B FD 21 02 00   [14]   99 	ld	iy,#2
+   003F FD 39         [15]  100 	add	iy,sp
+   0041 FD 7E 00      [19]  101 	ld	a,0 (iy)
+   0044 3D            [ 4]  102 	dec	a
+   0045 20 0C         [12]  103 	jr	NZ,00104$
+   0047 FD 7E 01      [19]  104 	ld	a,1 (iy)
+   004A B7            [ 4]  105 	or	a, a
+   004B 20 06         [12]  106 	jr	NZ,00104$
+                            107 ;usart.c:18: _usart->LCR.even_parity = 1;
+   004D 7E            [ 7]  108 	ld	a,(hl)
+   004E F6 10         [ 7]  109 	or	a,#0x10
+   0050 77            [ 7]  110 	ld	(hl),a
+   0051 18 17         [12]  111 	jr	00105$
+   0053                     112 00104$:
+                            113 ;usart.c:20: else if (mode == USART_PARITY_ODD) {
+   0053 FD 21 02 00   [14]  114 	ld	iy,#2
+   0057 FD 39         [15]  115 	add	iy,sp
+   0059 FD 7E 00      [19]  116 	ld	a,0 (iy)
+   005C D6 02         [ 7]  117 	sub	a, #0x02
+   005E 20 0A         [12]  118 	jr	NZ,00105$
+   0060 FD 7E 01      [19]  119 	ld	a,1 (iy)
+   0063 B7            [ 4]  120 	or	a, a
+   0064 20 04         [12]  121 	jr	NZ,00105$
+                            122 ;usart.c:21: _usart->LCR.even_parity = 0;
+   0066 7E            [ 7]  123 	ld	a,(hl)
+   0067 E6 EF         [ 7]  124 	and	a,#0xef
+   0069 77            [ 7]  125 	ld	(hl),a
+   006A                     126 00105$:
+                            127 ;usart.c:24: _usart->LCR.parity = (mode == USART_PARITY_NONE) ? 0 : 1;
+   006A 2Ar00r00      [16]  128 	ld	hl,(__usart)
+   006D 01 04 00      [10]  129 	ld	bc,#0x0004
+   0070 09            [11]  130 	add	hl,bc
+   0071 FD 21 02 00   [14]  131 	ld	iy,#2
+   0075 FD 39         [15]  132 	add	iy,sp
+   0077 FD 7E 00      [19]  133 	ld	a,0 (iy)
+   007A 07            [ 4]  134 	rlca
+   007B 07            [ 4]  135 	rlca
+   007C 07            [ 4]  136 	rlca
+   007D E6 F8         [ 7]  137 	and	a,#0xf8
+   007F E6 08         [ 7]  138 	and	a,#0x08
+   0081 4F            [ 4]  139 	ld	c,a
+   0082 7E            [ 7]  140 	ld	a,(hl)
+   0083 E6 F7         [ 7]  141 	and	a,#0xf7
+   0085 B1            [ 4]  142 	or	a,c
+   0086 77            [ 7]  143 	ld	(hl),a
+   0087 C9            [10]  144 	ret
+                            145 ;usart.c:27: void usart_set_stop_bits(int count)
+                            146 ;	---------------------------------
+                            147 ; Function usart_set_stop_bits
+                            148 ; ---------------------------------
+   0088                     149 _usart_set_stop_bits::
+                            150 ;usart.c:29: _usart->LCR.stop_bits = (count == USART_STOP_BITS_1) ? 0 : 1;
+   0088 ED 4Br00r00   [20]  151 	ld	bc,(__usart)
+   008C 03            [ 6]  152 	inc	bc
+   008D 03            [ 6]  153 	inc	bc
+   008E 03            [ 6]  154 	inc	bc
+   008F 03            [ 6]  155 	inc	bc
+   0090 FD 21 02 00   [14]  156 	ld	iy,#2
+   0094 FD 39         [15]  157 	add	iy,sp
+   0096 FD 7E 00      [19]  158 	ld	a,0 (iy)
+   0099 D6 0A         [ 7]  159 	sub	a, #0x0a
+   009B 20 0A         [12]  160 	jr	NZ,00103$
+   009D FD 7E 01      [19]  161 	ld	a,1 (iy)
+   00A0 B7            [ 4]  162 	or	a, a
+   00A1 20 04         [12]  163 	jr	NZ,00103$
+   00A3 3E 01         [ 7]  164 	ld	a,#0x01
+   00A5 18 01         [12]  165 	jr	00104$
+   00A7                     166 00103$:
+   00A7 AF            [ 4]  167 	xor	a,a
+   00A8                     168 00104$:
+   00A8 EE 01         [ 7]  169 	xor	a, #0x01
+   00AA 87            [ 4]  170 	add	a, a
+   00AB 87            [ 4]  171 	add	a, a
+   00AC E6 04         [ 7]  172 	and	a,#0x04
+   00AE 6F            [ 4]  173 	ld	l,a
+   00AF 0A            [ 7]  174 	ld	a,(bc)
+   00B0 E6 FB         [ 7]  175 	and	a,#0xfb
+   00B2 B5            [ 4]  176 	or	a,l
+   00B3 02            [ 7]  177 	ld	(bc),a
+   00B4 C9            [10]  178 	ret
+                            179 ;usart.c:32: void usart_word_length(int length)
+                            180 ;	---------------------------------
+                            181 ; Function usart_word_length
+                            182 ; ---------------------------------
+   00B5                     183 _usart_word_length::
+                            184 ;usart.c:34: _usart->LCR.word_length = length;
+   00B5 2Ar00r00      [16]  185 	ld	hl,(__usart)
+   00B8 01 04 00      [10]  186 	ld	bc,#0x0004
+   00BB 09            [11]  187 	add	hl,bc
+   00BC FD 21 02 00   [14]  188 	ld	iy,#2
+   00C0 FD 39         [15]  189 	add	iy,sp
+   00C2 FD 7E 00      [19]  190 	ld	a,0 (iy)
+   00C5 E6 03         [ 7]  191 	and	a,#0x03
+   00C7 4F            [ 4]  192 	ld	c,a
+   00C8 7E            [ 7]  193 	ld	a,(hl)
+   00C9 E6 FC         [ 7]  194 	and	a,#0xfc
+   00CB B1            [ 4]  195 	or	a,c
+   00CC 77            [ 7]  196 	ld	(hl),a
+   00CD C9            [10]  197 	ret
+                            198 ;usart.c:37: void usart_set_autoflow(int mode)
+                            199 ;	---------------------------------
+                            200 ; Function usart_set_autoflow
+                            201 ; ---------------------------------
+   00CE                     202 _usart_set_autoflow::
+                            203 ;usart.c:39: _usart->MCR.autoflow = (mode == USART_AUTOFLOW_OFF) ? 0 : 1;
+   00CE 2Ar00r00      [16]  204 	ld	hl,(__usart)
+   00D1 01 0C 00      [10]  205 	ld	bc,#0x000c
+   00D4 09            [11]  206 	add	hl,bc
+   00D5 FD 21 02 00   [14]  207 	ld	iy,#2
+   00D9 FD 39         [15]  208 	add	iy,sp
+   00DB FD 7E 00      [19]  209 	ld	a,0 (iy)
+   00DE E6 01         [ 7]  210 	and	a,#0x01
+   00E0 4F            [ 4]  211 	ld	c,a
+   00E1 7E            [ 7]  212 	ld	a,(hl)
+   00E2 E6 FE         [ 7]  213 	and	a,#0xfe
+   00E4 B1            [ 4]  214 	or	a,c
+   00E5 77            [ 7]  215 	ld	(hl),a
+                            216 ;usart.c:40: _usart->MCR.data_terminal_ready = (mode == USART_AUTOFLOW_ALL);
+   00E6 2Ar00r00      [16]  217 	ld	hl,(__usart)
+   00E9 01 05 00      [10]  218 	ld	bc,#0x0005
+   00EC 09            [11]  219 	add	hl,bc
+   00ED FD 7E 00      [19]  220 	ld	a,0 (iy)
+   00F0 D6 03         [ 7]  221 	sub	a, #0x03
+   00F2 20 0A         [12]  222 	jr	NZ,00103$
+   00F4 FD 7E 01      [19]  223 	ld	a,1 (iy)
+   00F7 B7            [ 4]  224 	or	a, a
+   00F8 20 04         [12]  225 	jr	NZ,00103$
+   00FA 3E 01         [ 7]  226 	ld	a,#0x01
+   00FC 18 01         [12]  227 	jr	00104$
+   00FE                     228 00103$:
+   00FE AF            [ 4]  229 	xor	a,a
+   00FF                     230 00104$:
+   00FF E6 01         [ 7]  231 	and	a,#0x01
+   0101 4F            [ 4]  232 	ld	c,a
+   0102 7E            [ 7]  233 	ld	a,(hl)
+   0103 E6 FE         [ 7]  234 	and	a,#0xfe
+   0105 B1            [ 4]  235 	or	a,c
+   0106 77            [ 7]  236 	ld	(hl),a
+   0107 C9            [10]  237 	ret
+                            238 ;usart.c:43: inline void usart_init(uint16_t baudrate, int parity, int stop_bits)
+                            239 ;	---------------------------------
+                            240 ; Function usart_init
+                            241 ; ---------------------------------
+   0108                     242 _usart_init::
+                            243 ;usart.c:45: usart_set_baudrate(baudrate);
+   0108 C1            [10]  244 	pop	bc
+   0109 E1            [10]  245 	pop	hl
+   010A E5            [11]  246 	push	hl
+   010B C5            [11]  247 	push	bc
+   010C E5            [11]  248 	push	hl
+   010D CDr00r00      [17]  249 	call	_usart_set_baudrate
+   0110 F1            [10]  250 	pop	af
+                            251 ;usart.c:46: usart_set_parity(parity);
+   0111 21 04 00      [10]  252 	ld	hl, #4
+   0114 39            [11]  253 	add	hl, sp
+   0115 4E            [ 7]  254 	ld	c, (hl)
+   0116 23            [ 6]  255 	inc	hl
+   0117 46            [ 7]  256 	ld	b, (hl)
+   0118 C5            [11]  257 	push	bc
+   0119 CDr34r00      [17]  258 	call	_usart_set_parity
+   011C F1            [10]  259 	pop	af
+                            260 ;usart.c:47: usart_set_stop_bits(stop_bits);
+   011D 21 06 00      [10]  261 	ld	hl, #6
+   0120 39            [11]  262 	add	hl, sp
+   0121 4E            [ 7]  263 	ld	c, (hl)
+   0122 23            [ 6]  264 	inc	hl
+   0123 46            [ 7]  265 	ld	b, (hl)
+   0124 C5            [11]  266 	push	bc
+   0125 CDr88r00      [17]  267 	call	_usart_set_stop_bits
+                            268 ;usart.c:48: usart_set_autoflow(USART_AUTOFLOW_OFF);
+   0128 21 00 00      [10]  269 	ld	hl, #0x0000
+   012B E3            [19]  270 	ex	(sp),hl
+   012C CDrCEr00      [17]  271 	call	_usart_set_autoflow
+   012F F1            [10]  272 	pop	af
+   0130 C9            [10]  273 	ret
+                            274 ;usart.c:51: void usart_transmit(uint8_t data)
+                            275 ;	---------------------------------
+                            276 ; Function usart_transmit
+                            277 ; ---------------------------------
+   0131                     278 _usart_transmit::
+                            279 ;usart.c:53: _usart->buffer = data;
+   0131 2Ar00r00      [16]  280 	ld	hl,(__usart)
+   0134 FD 21 02 00   [14]  281 	ld	iy,#2
+   0138 FD 39         [15]  282 	add	iy,sp
+   013A FD 7E 00      [19]  283 	ld	a,0 (iy)
+   013D 77            [ 7]  284 	ld	(hl),a
+                            285 ;usart.c:54: while (_usart->LSR.transmitter_holder_empty == 0); // wait
+   013E                     286 00101$:
+   013E 2Ar00r00      [16]  287 	ld	hl,(__usart)
+   0141 01 0D 00      [10]  288 	ld	bc,#0x000d
+   0144 09            [11]  289 	add	hl,bc
+   0145 7E            [ 7]  290 	ld	a,(hl)
+   0146 07            [ 4]  291 	rlca
+   0147 07            [ 4]  292 	rlca
+   0148 07            [ 4]  293 	rlca
+   0149 30 F3         [12]  294 	jr	NC,00101$
+   014B C9            [10]  295 	ret
+                            296 ;usart.c:57: uint8_t usart_receive()
+                            297 ;	---------------------------------
+                            298 ; Function usart_receive
+                            299 ; ---------------------------------
+   014C                     300 _usart_receive::
+                            301 ;usart.c:59: return _usart->buffer;
+   014C 2Ar00r00      [16]  302 	ld	hl,(__usart)
+   014F 6E            [ 7]  303 	ld	l,(hl)
+   0150 C9            [10]  304 	ret
+                            305 ;usart.c:62: int usart_write(uint8_t *data, size_t size)
+                            306 ;	---------------------------------
+                            307 ; Function usart_write
+                            308 ; ---------------------------------
+   0151                     309 _usart_write::
+   0151 DD E5         [15]  310 	push	ix
+   0153 DD 21 00 00   [14]  311 	ld	ix,#0
+   0157 DD 39         [15]  312 	add	ix,sp
+   0159 F5            [11]  313 	push	af
+                            314 ;usart.c:64: uint8_t *dp = data;
+   015A DD 7E 04      [19]  315 	ld	a,4 (ix)
+   015D DD 77 FE      [19]  316 	ld	-2 (ix),a
+   0160 DD 7E 05      [19]  317 	ld	a,5 (ix)
+   0163 DD 77 FF      [19]  318 	ld	-1 (ix),a
+                            319 ;usart.c:66: while (size--) {
+   0166 DD 4E 06      [19]  320 	ld	c,6 (ix)
+   0169 DD 46 07      [19]  321 	ld	b,7 (ix)
+   016C                     322 00104$:
+   016C 59            [ 4]  323 	ld	e, c
+   016D 50            [ 4]  324 	ld	d, b
+   016E 0B            [ 6]  325 	dec	bc
+   016F 7A            [ 4]  326 	ld	a,d
+   0170 B3            [ 4]  327 	or	a,e
+   0171 28 1E         [12]  328 	jr	Z,00106$
+                            329 ;usart.c:67: _usart->buffer = *(dp++);
+   0173 ED 5Br00r00   [20]  330 	ld	de,(__usart)
+   0177 E1            [10]  331 	pop	hl
+   0178 E5            [11]  332 	push	hl
+   0179 7E            [ 7]  333 	ld	a,(hl)
+   017A DD 34 FE      [23]  334 	inc	-2 (ix)
+   017D 20 03         [12]  335 	jr	NZ,00126$
+   017F DD 34 FF      [23]  336 	inc	-1 (ix)
+   0182                     337 00126$:
+   0182 12            [ 7]  338 	ld	(de),a
+                            339 ;usart.c:68: while (_usart->LSR.transmitter_empty);
+   0183                     340 00101$:
+   0183 2Ar00r00      [16]  341 	ld	hl,(__usart)
+   0186 11 0D 00      [10]  342 	ld	de,#0x000d
+   0189 19            [11]  343 	add	hl,de
+   018A 7E            [ 7]  344 	ld	a,(hl)
+   018B 07            [ 4]  345 	rlca
+   018C 07            [ 4]  346 	rlca
+   018D 30 DD         [12]  347 	jr	NC,00104$
+   018F 18 F2         [12]  348 	jr	00101$
+   0191                     349 00106$:
+                            350 ;usart.c:72: return size;
+   0191 69            [ 4]  351 	ld	l, c
+   0192 60            [ 4]  352 	ld	h, b
+   0193 DD F9         [10]  353 	ld	sp, ix
+   0195 DD E1         [14]  354 	pop	ix
+   0197 C9            [10]  355 	ret
+                            356 ;usart.c:75: int usart_read(uint8_t *buffer, size_t count)
+                            357 ;	---------------------------------
+                            358 ; Function usart_read
+                            359 ; ---------------------------------
+   0198                     360 _usart_read::
+   0198 DD E5         [15]  361 	push	ix
+   019A DD 21 00 00   [14]  362 	ld	ix,#0
+   019E DD 39         [15]  363 	add	ix,sp
+   01A0 21 FA FF      [10]  364 	ld	hl,#-6
+   01A3 39            [11]  365 	add	hl,sp
+   01A4 F9            [ 6]  366 	ld	sp,hl
+                            367 ;usart.c:77: uint8_t *bp = buffer;
+   01A5 DD 7E 04      [19]  368 	ld	a,4 (ix)
+   01A8 DD 77 FA      [19]  369 	ld	-6 (ix),a
+   01AB DD 7E 05      [19]  370 	ld	a,5 (ix)
+   01AE DD 77 FB      [19]  371 	ld	-5 (ix),a
+                            372 ;usart.c:80: while (count--) {
+   01B1 DD 4E 06      [19]  373 	ld	c,6 (ix)
+   01B4 DD 46 07      [19]  374 	ld	b,7 (ix)
+   01B7 DD 36 FC 00   [19]  375 	ld	-4 (ix),#0x00
+   01BB DD 36 FD 00   [19]  376 	ld	-3 (ix),#0x00
+   01BF                     377 00105$:
+   01BF 59            [ 4]  378 	ld	e, c
+   01C0 50            [ 4]  379 	ld	d, b
+   01C1 0B            [ 6]  380 	dec	bc
+   01C2 7A            [ 4]  381 	ld	a,d
+   01C3 B3            [ 4]  382 	or	a,e
+   01C4 28 48         [12]  383 	jr	Z,00107$
+                            384 ;usart.c:81: *(bp++) = _usart->buffer;
+   01C6 2Ar00r00      [16]  385 	ld	hl,(__usart)
+   01C9 5E            [ 7]  386 	ld	e,(hl)
+   01CA E1            [10]  387 	pop	hl
+   01CB E5            [11]  388 	push	hl
+   01CC 73            [ 7]  389 	ld	(hl),e
+   01CD DD 34 FA      [23]  390 	inc	-6 (ix)
+   01D0 20 03         [12]  391 	jr	NZ,00123$
+   01D2 DD 34 FB      [23]  392 	inc	-5 (ix)
+   01D5                     393 00123$:
+   01D5 ED 5Br00r00   [20]  394 	ld	de,(__usart)
+                            395 ;usart.c:83: if (_usart->LSR.framing_error || _usart->LSR.parity_error) {
+   01D9 21 0D 00      [10]  396 	ld	hl,#0x000d
+   01DC 19            [11]  397 	add	hl,de
+   01DD DD 75 FE      [19]  398 	ld	-2 (ix),l
+   01E0 DD 74 FF      [19]  399 	ld	-1 (ix),h
+   01E3 DD 6E FE      [19]  400 	ld	l,-2 (ix)
+   01E6 DD 66 FF      [19]  401 	ld	h,-1 (ix)
+   01E9 7E            [ 7]  402 	ld	a,(hl)
+   01EA 0F            [ 4]  403 	rrca
+   01EB 0F            [ 4]  404 	rrca
+   01EC 0F            [ 4]  405 	rrca
+   01ED E6 01         [ 7]  406 	and	a,#0x01
+   01EF 20 0D         [12]  407 	jr	NZ,00101$
+   01F1 DD 6E FE      [19]  408 	ld	l,-2 (ix)
+   01F4 DD 66 FF      [19]  409 	ld	h,-1 (ix)
+   01F7 7E            [ 7]  410 	ld	a,(hl)
+   01F8 0F            [ 4]  411 	rrca
+   01F9 0F            [ 4]  412 	rrca
+   01FA E6 01         [ 7]  413 	and	a,#0x01
+   01FC 28 06         [12]  414 	jr	Z,00102$
+   01FE                     415 00101$:
+                            416 ;usart.c:84: bp--; // delete last byte (?)
+   01FE E1            [10]  417 	pop	hl
+   01FF E5            [11]  418 	push	hl
+   0200 2B            [ 6]  419 	dec	hl
+   0201 E3            [19]  420 	ex	(sp), hl
+   0202 18 BB         [12]  421 	jr	00105$
+   0204                     422 00102$:
+                            423 ;usart.c:86: read_count++;
+   0204 DD 34 FC      [23]  424 	inc	-4 (ix)
+   0207 20 B6         [12]  425 	jr	NZ,00105$
+   0209 DD 34 FD      [23]  426 	inc	-3 (ix)
+   020C 18 B1         [12]  427 	jr	00105$
+   020E                     428 00107$:
+                            429 ;usart.c:90: return read_count;
+   020E C1            [10]  430 	pop	bc
+   020F E1            [10]  431 	pop	hl
+   0210 E5            [11]  432 	push	hl
+   0211 C5            [11]  433 	push	bc
+   0212 DD F9         [10]  434 	ld	sp, ix
+   0214 DD E1         [14]  435 	pop	ix
+   0216 C9            [10]  436 	ret
+                            437 	.area _CODE
+                            438 	.area _INITIALIZER
+   0000                     439 __xinit___usart:
+   0000 00 40               440 	.dw #0x4000
+                            441 	.area _CABS (ABS)