mangavalk/lcdproc
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* Automatically exclude the pin for switchable backlight from keypad scanning

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in the 4bit and 8bit wiring. This fixes problems with flickering backlight if
  a slow parallel port is used. IMPORTANT: This may require a hardware change!
* In code comments use the same line names as in the user's guide (Y1/X1
  instead of Y0/X0).
* Add documentation about hd44780-ftdi's 4bit mode.
This commit is contained in:
mmdolze
2010-01-18 22:24:59 +00:00
parent 6fba5cef68
commit 59f3cbdb45
6 changed files with 208 additions and 64 deletions
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server/drivers/hd44780-4bit.c
+39 -16
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@@ -34,19 +34,29 @@
* Keypad connection (optional):
* Some diodes and resistors are needed, see further documentation.
* printer port keypad
* D0 (2) Y0
* D1 (3) Y1
* D2 (4) Y2
* D3 (5) Y3
* D4 (6) Y4
* D5 (7) Y5
* D0 (2) Y1
* D1 (3) Y2
* D2 (4) Y3
* D3 (5) Y4
* D4 (6) Y5
*
* With a backlight or three displays, 4 additional rows are possible:
* nSTRB (1) Y6
* nLF (14) Y7
* INIT (16) Y8
* nSEL (17) Y9
*
* With only two controllers and no backlight, 5 additional rows are possible:
* D5 (7) Y6
* nSTRB (1) Y7
* nLF (14) Y8
* INIT (16) Y9
* nSEL (17) Y10
*
* Colums return lines are the same for all configurations:
* nACK (10) X0
* BUSY (11) X1
* PAPEREND (12 X2
* PAPEREND (12) X2
* SELIN (13) X3
* nFAULT (15) X4
*
@@ -125,7 +135,7 @@ hd_init_4bit(Driver *drvthis)
port_out(p->port, 0x03);
if (p->delayBus) hd44780_functions->uPause(p, 1);
/* We'll now send 0x03 a coulpe of times,
/* We'll now send 0x03 a coulpe of times,
* which is in fact (FUNCSET | IF_8BIT) >> 4 */
port_out(p->port, enableLines | 0x03);
port_out(p->port + 2, ALLEXT ^ OUTMASK);
@@ -268,22 +278,35 @@ unsigned char lcdstat_HD44780_readkeypad(PrivateData *p, unsigned int YData)
{
unsigned char readval;
// 10 bits output or 6 bits if >=3 displays
// Convert the positive logic to the negative logic on the LPT port
port_out(p->port, ~YData & 0x003F);
if (p->numDisplays<=3) {
// Can't combine >3 displays with >6 keypad output lines
/* If at most two controllers and NO backlight, 10 bits may be used */
if ((p->numDisplays <= 2) && (!p->have_backlight)) {
port_out(p->port, ~YData & 0x003F);
port_out(p->port + 2, (((~YData & 0x03C0) >> 6)) ^ OUTMASK);
}
else {
/*
* Else ignore D5, because it may be either backlight or EN3.
* Note: If three displays are used, have_backlight must be
* set to 'no' in the config.
*/
port_out(p->port, (~YData & 0x001F) | p->backlight_bit);
/*
* With at most three controllers or backlight 9 bits may be
* used.
*/
if (p->numDisplays<=3) {
port_out(p->port + 2, (((~YData & 0x01E0) >> 5)) ^ OUTMASK);
}
}
if (p->delayBus) p->hd44780_functions->uPause(p, 1);
// Read inputs
/* Read inputs */
readval = ~ port_in(p->port + 1) ^ INMASK;
// Put port back into idle state for backlight
/* Put port back into idle state for backlight */
port_out(p->port, p->backlight_bit);
// And convert value back (MSB first).
/* And convert value back (MSB first) */
return (((readval & FAULT) / FAULT <<4) | /* pin 15 */
((readval & SELIN) / SELIN <<3) | /* pin 13 */
((readval & PAPEREND) / PAPEREND <<2) | /* pin 12 */