diff options
Diffstat (limited to 'src/devices/machine/ie15.cpp')
-rw-r--r-- | src/devices/machine/ie15.cpp | 64 |
1 files changed, 32 insertions, 32 deletions
diff --git a/src/devices/machine/ie15.cpp b/src/devices/machine/ie15.cpp index 912f346fe09..438ffb1712b 100644 --- a/src/devices/machine/ie15.cpp +++ b/src/devices/machine/ie15.cpp @@ -2,12 +2,12 @@ // copyright-holders:Sergey Svishchev /*************************************************************************** - 15IE-00-013 Terminal + 15IE-00-013 Terminal - A serial (RS232 or current loop) green-screen terminal, mostly VT52 - compatible (no Hold Screen mode and no graphics character set). + A serial (RS232 or current loop) green-screen terminal, mostly VT52 + compatible (no Hold Screen mode and no graphics character set). - Alternate character set (selected by SO/SI chars) is Cyrillic. + Alternate character set (selected by SO/SI chars) is Cyrillic. ****************************************************************************/ @@ -416,32 +416,32 @@ void ie15_device::device_reset() } /* - Usable raster is 800 x 275 pixels (80 x 25 characters). 24 lines are - available to the user and 25th (topmost) line is the status line. - Status line, if enabled, displays current serial port speed, 16 setup - bits, and clock. There is no NVRAM, so setup bits are always 0 after - reset and clock starts counting at 0 XXX. - - No character attributes are available, but in 'display controls' mode - control characters stored in memory are shown as blinking chars. - - Character cell is 10 x 11; character generator provides 7 x 8 of that. - 3 extra horizontal pixels are always blank. Blinking cursor may be - displayed on 3 extra scan lines. - - On each scan line, video board draws 80 characters from any location - in video memory; this is used by firmware to provide instant scroll - and cursor, which is a character with code 0x7F stored in off-screen - memory. - - Video board output is controlled by - - control flag 0 "disable video": 0 == disable - - control flag 1 "cursor": 0 == if this scan line is one of extra 3, - enable video every 5 frames. - - control flag 3 "status line": 0 == current scan line is part of status line - - keyboard mode 'RED' ('display controls'): if character code is - less than 0x20 and RED is set, enable video every 5 frames; if RED is - unset, disable video. + Usable raster is 800 x 275 pixels (80 x 25 characters). 24 lines are + available to the user and 25th (topmost) line is the status line. + Status line, if enabled, displays current serial port speed, 16 setup + bits, and clock. There is no NVRAM, so setup bits are always 0 after + reset and clock starts counting at 0 XXX. + + No character attributes are available, but in 'display controls' mode + control characters stored in memory are shown as blinking chars. + + Character cell is 10 x 11; character generator provides 7 x 8 of that. + 3 extra horizontal pixels are always blank. Blinking cursor may be + displayed on 3 extra scan lines. + + On each scan line, video board draws 80 characters from any location + in video memory; this is used by firmware to provide instant scroll + and cursor, which is a character with code 0x7F stored in off-screen + memory. + + Video board output is controlled by + - control flag 0 "disable video": 0 == disable + - control flag 1 "cursor": 0 == if this scan line is one of extra 3, + enable video every 5 frames. + - control flag 3 "status line": 0 == current scan line is part of status line + - keyboard mode 'RED' ('display controls'): if character code is + less than 0x20 and RED is set, enable video every 5 frames; if RED is + unset, disable video. */ void ie15_device::draw_scanline(uint32_t *p, uint16_t offset, uint8_t scanline) @@ -506,9 +506,9 @@ void ie15_device::update_leds() } /* - VBlank is active for 3 topmost on-screen rows and 1 at the bottom; however, control flag 3 + VBlank is active for 3 topmost on-screen rows and 1 at the bottom; however, control flag 3 overrides VBlank, - allowing status line to be switched on and off. + allowing status line to be switched on and off. */ void ie15_device::scanline_callback() { |