iSBXTM 270 Walkthrough 1/"

2 " i270.c - iSBX270 device driver 3"

AP·184

4 " - implements terminal device driver for the iSBX270 character 5" graphics video display controller

6"

7 • See also: c270.c - i270 configuration 8 " i270.h - i270 include files 9"

10 " Notes on this driver:

11 " (1) The driver supports the keyboard interface and display 12" in scroll mode or page mode

13 * (2)AII manual references in the comments are to the iSBX270 14" Video Display Terminal Controller Board Hardware Reference 15 * Manual, order number 143444-001.

16 *f 17

18 #include " . .lhfparam.h"

19 #include " . .lhfuser.h"

20 #include " . .lhftty.h"

21 #include " . .lhIi270.h"

22

23 extern struct 24

25 short i270-alive;

26 struct tty i270tty;

27 int c..state;

28 291*

30" i270initO

i270cfg i270cfg; 1* configuration structure" f 1* board alive flag" f

1* tty structure * f

f" state variable used for escape sequences * f

31 *. - tests for presence of the iSBX270, and reports its presence 32 * or absence

33 * -initializes 270 for the configured modes of operation 34 * - this routine is called very early in the system initialization 35 *f

36

37 i270initO 38 (

39 short mode;

40 int rststat;

41 421*

43 * The sequence below sends a reset command to the 270. The 44 * algorithm is based on the flowchart, page 3-8 of the manual.

45 * We perform the additional task of determining if the board is 46' present or not.

47 *f 48 c..state ⁰⁼ 0;

49 rststat

=

rst270(); 1* reset 270 *f 50 if (rststat = = RSTERR)

f"

* Board not found.

"f 51 52 53 54 55 56 57 58

printf("iSBX 270 board port %x NOT found.O, i270cfg.c_data);

i270-alive

=

I270DEAD;

return;

2-153 280041-001

AP-184

59 } 60 else (

61 printf("iSBX 270 board port %x found.O, i270cfg.c_data);

62 i270_alive = I270LIVES;

63 } 64 651*

66 • Board lives, so set it up in the configuration specified.

67 • NIMASK is anded with everything to clear any bits which 68 • aren't implemented.

69 • Once we reach this point, we'll assume that the board is 70 • alive to some extent, so we'll just concern ourselves w.th 71 * getting through the initialization; but we can't afford to 72 • get hung up if the firmware is acting funny. Our approach 73 * will be to protect ourselves against infinite loops, but not 74 * check for error conditions or worry about reporting them.

75 *1 76

77 mode = (i270cfg.c_keybrd

I

i270cfg.clpen

I

i270cfg.cdma

I

78 i270cfg.cmode

I

IBEINT

I

(i270cfg.c_cursor & CURMSK)) 79 &NIMASK;

80 mode270(mode);

81 } 82 831*

84 • rst2700 - resets the 270 board 85 *1

86 87 rst2700 88 (

89 unsigned i;

90 91/*

92 * Clear out any garbage in input and output buffers.

93 * i is a safety valve in case the board is not here and 94 * we read a 1 in the IBF bit - we'll take care of the 95 • presence or absence of the board later - for now we just 96 * need to get out of this loop.

97 *1 98 99i = 0;

100 while «in-270(i270cfg.cstat) & I270IBF) &&

0+ +

< 30000)) ( 101 if (in_270(i270cfg.c_stat) & I2700BF)

102 in_270(i270cfg.cdata); 1* dummy data *1 103 }

104 ouL270(i270cfg.cstat, I270RST); 1* reset it *1 105

1061*

107 * We'll look for some sign oflife from the 270. If 108 • it's not there, we'll either blow right through the 109 • loop, or get stuck in it forever. We'll limit

110 * forever to 30000 iterations, and check for a count of 111 * 0 or

>

30000 upon terminating the loop - either one is 112 • then interpreted as a sign that the board isn't here.

113 *1 114 115 i = O·

116 while' «in-270(i270cfg.c_stat) &

117 (I2700BF

I

I270IBF

I

I270BUS)) && (j

+ + <

30000)) ( 118 if (in_270(i270cfg.cstat) & 12700BF)

2-154 280041-001

AP-184

119 in-270(i270cfg.c--"ata); 1* dummy input */

120 }

121 if((i

= =

0)

I

(i

>

30000» return RSTERR;

122 else return RSTOK;

123}

124 125/*

126 * mode270(mode) - sets VOTC mode for 270 board to specified mode 127 */

128

129 mode270(mode) 130 short mode;

13l{

132 unsigned i;

133 134/*

135 * First, go into null busy wait until we can stick another 136 • command into the input buffer - once again, i is used as 137 * an escape in case the firmware on the 270 is acting goofy.

138 *f 139 i = O'

140 while' ((in_270(i270cfg.c...stat) & I270IBF) && (i+ +

<

30000»;

141 1421*

143 * Now we can issue a new command - we do a set VOTC mode.

144 *f 145

146 ouL270(i270cfg.c...stat, I270SM);

147 1481*

149 * Wait until the 270 can accept the parameter.

150 *f 151 152 i = O'

153 while' (((in-270(i270cfg.c_stat) &

154 (I2700BF II270IBF II270BUS» ! = I270BUS) && (i+ +

<

30000» ( 155 if (in-270(i270cfg.c...stat) & I2700BF)

156 in-270(i270cfg.c_data); 1* dummy input ifOBF set *f 157}

158 ouL270(i270cfg.c_data, mode);

159}

160 1611*

162 * i270open(dev) - opens dev 163 *f

164 '

165i270open(dev) 166 dev_t dey;

167 (

168 int unit, i270startO;

169 struct tty *tp;

170 1711*

172 • First check to make sure that board is alive - if not, 173 * mark error and return.

174 *f 175

176 if (i270....alive

==

I270DEAO) {

177 u. u_error = ENXIO; 1* no such device or address * f 178 return;

2-155 280041-001

179 } 180 1811*

182 ° tp will point to the tty structure 183 *f

184

185 tp = &i270tty;

186 1871*

AP-184

188 ° Check for 270 already being exclusively opened 189 of

190

191 if «tp->Lstate & XCLUDE) && u.u_uid) { 192 u.u_error = EBUSY;

193 return;

194 } 195 1961*

197 ° Set up fields in tty structure.

198

*'

199

200 tp->Laddr = (caddr_t)i270cfg.c_data;

r

io base address

*'

201 tp- > Loproc = i270start; 1* routine to start output

*'

202 203

,*

204 * If this is first open ...

205

*'

206

207 if «tp- > Lstate & ISOPEN) = = 0) {

208, ttychars(tp);

r

sets special characters

0,

209 tp-> Lispeed = tp->Lospeed = 9600; 1* baud rate meaningless

0,

210 tp- > Lflags = ODDP 1 EVENP 1 ECHO 1 CRMOD; 1* should add no

211 tab expansion here

*'

212 }

213 tp->Lstate

1=

^CARR_ON;

214 ttyopen(dev, tp);

215 } 216 2171*

218 * i270close(dev, flag) 219

0,

220

221 i270close(dev) 222 dev_t dey;

223 (

224 struct tty °tp;

225

226 tp = &i270tty;

227 ttyclose(tp);

228 tp- >Laddr = (caddr _t) 0; 1* forget base address * , 229 }

230

231i270read(dev) 232 dev_t dey;

233 (

234 struct tty °tp;

235

236 tp = &i270tty;

237 ttread(tp);

238}

2-156 280041-001

inter

239

240 i270write (dev) 241 dev_t dey;

242 (

243 struct tty *tp;

244

245 tp = &i270tty;

246 ttwrite(tp);

247 ) 248

249 i270iintr(JeveI) 250 int level;

251 (

252 struct tty *tp;

253 short status, chr;

254

255 tp = &i270tty;

256 status = inb(i270cfg.c-stat);

257 chr = inb(i270cfg.cdata);

258 if (status & I270KDR)

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259 ttyinput(chr, tp); 1* only if a valid keyboard hit *f 260 )

261

262 i270ointr(JeveI) 263 int level;

264 ( 265 struct 266

tty 267 tp = &i270tty;

*tp;

268 if (tp- > Lstate & BUSY) ( 269 tp- > Lstate & = - BUSY;

270 ttstart(tp);

271 if «tp-> Lstate & ASLEEP) &&

272 (tp-> Loutq.c_cc

<

= TTLOWAT»

273 wakeup«caddLt)&tp-> Loutq);

274 ) 275 }

276 int ttrstrtO;

277 extern char par tab [];

278

279 i270start(tp) 280 struc( tty *tp;

281 ( 282 int e,s;

283 short mode;

284 285 286 287 288

s = sp150;

if (tp-> Lstate & (TIMEOUT IBUSY» ( splx(s);

return;

289 }

290 if «c=getc(&tp->Loutq» >= 0) ( 291 tp->Lstatel= BUSY;

292 splx (s);

293 switch (c-state) ( 294 case 0:

295' if(c==Oxlb)(

296 #ifdefDEBUG 297

298 #endif

printf("O %xO, c);

2-157 280041-001

inter

timeout(ttrstrt, (caddU}tp, (c & Ox7f»;

return;

break;

case 1:

switch (c) case '=':

1* cursor address sequence

*'

319 #ifdefDEBUG

1* visual attribute sequence "' printf("O 00000);

335 outb(i270cfg.c_data, 0);

336 c-state = 6;

352 outb(i270cfg.c-stat, I270SCP);

353 c_state = 4;

inter

^AP-184

outb(i270cfg.c_data, «c & Ox30

I

Ox80»;

c_state = 0;

break;

case 4:

outb(i270cfg.c_data, (c - Ox30»;

c-state = 5;

break;

case 5:

outb(i270cfg.c_data, (c - Ox30»;

c-state = 0;

i270cfg,cdma

I

i270cfgLmode

I

378

IBEINT

I

(i270cfg.c_cursor & CURMSK»

&NIMASK;

* just output character and go back to state 0

-* nothing special, just didn't want to flip into a

* special mode as a result of this graphics character

*f

397 i270ioctl(dev, cmd, addr, flag) 398 caddLt addr;

* No ioctl functions supported

*f

409 else u.u_error = ENOTTY;

410

I

411

412in-270(port) 413 unsigned port;

414 (

415 unsigned i;

416

417( for (i=0; i

<

DELAY270; i+ +);

418 return (short) inb(port);

2-159 280041-001

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Dans le document LITERATURE In addition to the product line handbooks listed below, the (Page 169-176)