Here are the features of the Open ROMs not found in the original ROMs from the 80s (many of them are configurable during compilation):
-
improved keyboard scanning, resistant to ghosting and joystick interference, supports additional C128 keys
-
joystick can be used to move text cursor
-
pre-defined function keys
-
JiffyDOS and DolphinDOS protocols support
-
DOS wedge (direct mode only) -
@<unit_number>,@<command>,@$[mask],@<unit_number>$,@<unit_number>$[mask]@ -
BASIC extensions, see the documentation
-
extended / tweaked
LOAD/VERIFYcommands- start/end addresses are displayed, in the Final cartridge style
- command with just the file name tries to use the last device if it's number seems sane; otherwise uses 8
- command without parameters tries to load first file from drive chosen as above
-
LISTcommand should never damage the screen if trying to list memory content which is not a BASIC program -
high performance garbage collector
-
turbo tape load support (as device 7, or using
←L/←M, optionally with a file name), quite sophisticated: up to 250 blocks (can store bytes under I/O), on MEGA65 motherboard automatically adjusts itself for tape speed differences -
normal tape load error log is limited by free stack space only (no artificial limitation like in original ROMs)
-
tape format autodetection; normal vs turbo is mostly transparent to user
-
improved support for tape adapters (for using regular casette players and other audio devices instead of Datasette) and emulators
-
built-in tape head align tool (only feasible to use on machines with extended memory, like MEGA65)
-
uses RAM under ROM and I/O: 51199 bytes free (up to
$CFFF) by default, but 61438 is also possible -
cold/warm start silences multiple SID chips
-
warm start due to BRK prints out the instruction address
NOTE: extra features and their syntax can change in the future!
The following ROM features are currently missing and are not planned due to space considerations:
- full tape support - VERIFY, SAVE, sequential files; tape is considered a legacy medium, so its support is going to be limited
- mock 6551 emulation - this only complicates the RS-232 support for original ROMs, probably noone needs it
The following ROM features are currently missing:
- most BASIC commands
- BASIC integer/float variables/arrays (strings work now, with the exception of undefined arrays)
- BASIC expression handling (again, strings should work now)
- RS-232 support
- NMI handling is incomplete
| Driver | Status | Remarks |
|---|---|---|
| C64 | DONE | |
| C128 | DONE | |
| MEGA65 | PARTIAL | code mostly complete, but not tested yet |
| Driver | Status | Remarks |
|---|---|---|
| VIC-II | DONE | |
| 80 columns, VDC | NOT DONE | |
| 80 columns, MEGA65 | PARTIAL | no windowing mode and C65/M65 extra keys support |
- Tapuino
- Datasette
| Driver | Status | Remarks |
|---|---|---|
| normal | DONE | up to 202 blocks, like original ROM |
| turbo | DONE | up to 250 blocks, like the best implementations |
- SD2IEC, petSD+, µIEC
- Pi1541, Ultimate II
- most disk drives and printers
- some hard drives
| Driver | Status | Remarks |
|---|---|---|
| standard | DONE | |
| JiffyDOS | PARTIAL | LOAD needs improvement for better performance |
| ELoad v1 | NOT DONE | |
| DolphinDOS | DONE | |
| CIA burst mod | NOT DONE | |
| MEGA65 burst | NOT DONE |
- petSD+
- PET era disk drives and printers
- various scientific equipment
| Driver | Status | Remarks |
|---|---|---|
| CBM cartridge | NOT DONE |
| Driver | Status | Remarks |
|---|---|---|
| SD card | PARTIAL | work-in-progress, can already load files |
| floppy drive | NOT DONE | |
| ram disk | NOT DONE |
- modems (telephone, WiFi)
- parallel port printers
| Driver | Status | Remarks |
|---|---|---|
| UP2400 | NOT DONE | |
| UP9600 | NOT DONE | work started, not functional yet |
| ACIA 6551 | NOT DONE |
Status of the various APIs and variables from the original ROMs
For the current status of the low memory location implementation andd usage check this file. NOTE: available vector to certain routine does not mean that this routine is fully implemented!
| Entry | Unofficial | Name | Status | Remarks |
|---|---|---|---|---|
($0003) |
ADRAY1 |
NOT DONE | ||
($0005) |
ADRAY2 |
NOT DONE | ||
(00300) |
$E38B |
ERROR |
NOT DONE | |
(00302) |
$A483 |
MAIN |
NOT DONE | some implementation exists, but not connected here |
(00304) |
$A57C |
CHRNCH |
NOT DONE | |
(00306) |
$A71A |
QPLOP |
NOT DONE | some implementation exists, but not connected here |
(00308) |
$A7E4 |
GONE |
NOT DONE | some implementation exists, but not connected here |
(0030A) |
$AE86 |
EVAL |
NOT DONE | some implementation exists, but not connected here |
($A000) |
$E394 |
cold start | PARTIAL | |
($A002) |
$E3B7 |
warm start | PARTIAL |
Floating point mathematical routines - not official, but well known and broadly used. Note: there is an awful mess regarding naming (sometimes same name references different routines in different sources), so a custom naming scheme was applied.
| Address | Name | Status | Remarks |
|---|---|---|---|
$A9C4 |
convert_FAC1_to_INT |
NOT DONE | |
$AABC |
print_FAC1 |
NOT DONE | |
$AF7B |
compute_TI |
NOT DONE | |
$AF7E |
not named yet | NOT DONE | |
$AF87 |
not named yet | NOT DONE | |
$AF9A |
compute_ST |
NOT DONE | |
$B1AA |
FACINX |
NOT DONE | convert FAC1 to 16-bit signed integer |
$B1BF |
convert_FAC1_to_s16 |
NOT DONE | |
$B391 |
GIVAYF |
NOT DONE | 16-bit signed integer to FAC1 |
$B3A2 |
convert_Y_to_FAC1 |
NOT DONE | |
$B794 |
convert_A_to_FAC1 |
NOT DONE | |
$B7B5 |
STRVAL |
NOT DONE | imports string to FAC1 |
$B7F7 |
convert_FAC1_to_ADDR |
NOT DONE | |
$B849 |
add_HALF_FAC1 |
DONE | |
$B850 |
sub_MEM_FAC1 |
DONE | |
$B853 |
sub_FAC2_FAC1 |
DONE | |
$B862 |
add_align_exponents |
DONE | |
$B867 |
add_MEM_FAC1 |
DONE | |
$B86A |
add_FAC2_FAC1 |
DONE | |
$B8FE |
normal_FAC1 |
DONE | |
$B947 |
inv_FAC1_mantissa |
NOT DONE | |
$B9EA |
log_FAC1 |
NOT DONE | |
$BA28 |
mul_MEM_FAC1 |
DONE | |
$BA2B |
mul_FAC2_FAC1 |
DONE | |
$BA8C |
mov_MEM_FAC2 |
DONE | |
$BA90 |
get_FAC2_via_INDEX |
NOT DONE | |
$BAE2 |
mul10_FAC1 |
DONE | |
$BAFE |
div10_FAC1_p |
DONE | |
$BB0F |
div_MEM_FAC1 |
DONE | |
$BB12 |
div_FAC2_FAC1 |
DONE | |
$BBA2 |
mov_MEM_FAC1 |
DONE | |
$BBA6 |
get_FAC2_via_INDEX |
NOT DONE | |
$BBC7 |
mov_r_FAC1_TMP2 |
PARTIAL | not fully tested yet |
$BBCA |
mov_r_FAC1_TMP1 |
PARTIAL | not fully tested yet |
$BBD0 |
mov_r_FAC1_VAR |
PARTIAL | not fully tested yet |
$BBD4 |
mov_r_FAC1_MEM |
PARTIAL | not fully tested yet |
$BBFC |
mov_FAC2_FAC1 |
PARTIAL | not fully tested yet |
$BC0C |
mov_r_FAC1_FAC2 |
PARTIAL | not fully tested yet |
$BC0F |
mov_FAC1_FAC2 |
DONE | |
$BC1B |
round_FAC1 |
PARTIAL | not fully tested yet |
$BC2B |
sgn_FAC1_A |
DONE | |
$BC39 |
sgn_FAC1 |
NOT DONE | |
$BC3C |
convert_A_to_FAC1 |
NOT DONE | |
$BC44 |
convert_i16_to_FAC1 |
NOT DONE | |
$BC58 |
abs_FAC1 |
NOT DONE | |
$BC5B |
FCOMP |
NOT DONE | compare FAC1 with RAM location |
$BC9B |
QINT |
NOT DONE | convert FAC1 to 32 bit signed integer |
$BCCC |
int_FAC1 |
NOT DONE | |
$BCF3 |
FIN |
NOT DONE | imports string to FAC1, ignores spaces |
$BD7E |
FINLOG |
NOT DONE | |
$BDDD |
FOUT |
NOT DONE | outputs FAC1 to string at $0100 |
$BF71 |
sqr_FAC1 |
PARTIAL | needs sqr_FAC2 |
$BF74 |
sqr_FAC2 |
NOT DONE | |
$BF78 |
pwr_FAC2_MEM |
PARTIAL | needs pwr_FAC2_FAC1 |
$BF7B |
pwr_FAC2_FAC1 |
NOT DONE | |
$BFB4 |
toggle_sign_FAC1 |
DONE | |
$BFED |
exp_FAC1 |
NOT DONE | |
$E043 |
poly1_FAC1 |
NOT DONE | |
$E059 |
poly2_FAC1 |
NOT DONE | |
$E097 |
rnd_FAC1 |
DONE | |
$E09A |
rnd_A |
DONE | |
$E0BE |
rnd_generate |
DONE | |
$E264 |
cos_FAC1 |
NOT DONE | |
$E26B |
sin_FAC1 |
NOT DONE | some work already started |
$E2B4 |
tan_FAC1 |
NOT DONE | |
$E30E |
atn_FAC1 |
NOT DONE |
In addition to the routines, the following floating-number constants are available at their original locations:
| Address | Name | Status | Remarks |
|---|---|---|---|
$AEA8 |
const_PI |
DONE | π |
$B1A5 |
const_NEG_32768 |
DONE | -32768 |
$B9BC |
const_ONE |
DONE | 1.0 |
$B9D6 |
const_INV_SQR_2 |
DONE | 1.0 / sqr(2.0) |
$B9DB |
const_SQR_2 |
DONE | sqr(2.0) |
$B9E0 |
const_NEG_HALF |
DONE | -0.5 |
$B9E5 |
const_LOG_2 |
DONE | log_e(2.0) |
$BAF9 |
const_TEN |
DONE | 10.0 |
$BF11 |
const_HALF |
DONE | 0.5 |
$BFBF |
const_INV_LOG_2 |
DONE | 1.0 / log_e(2.0) |
$BFE8 |
const_ONE duplicate |
DONE | 1.0 |
$E2E0 |
const_HALF_PI |
DONE | PI / 2.0 |
$E2E5 |
const_DOUBLE_PI |
DONE | PI * 2.0 |
$E2EA |
const_QUARTER |
DONE | 0.25 |
$E309 |
const_DOUBLE_PI duplicate |
DONE | PI * 2.0 |
Not all of them - only these we want to have implemented.
| Address | Name | Status | Remarks |
|---|---|---|---|
$A004 |
revision str | DONE | |
$A408 |
REASON |
NOT DONE | |
$A453 |
(unknown) | NOT DONE | |
$A533 |
LINKPRG |
DONE | |
$A644 |
new | NOT DONE | |
$A659 |
set txt ptr | NOT DONE | |
$A68E |
RUNC |
DONE | |
$A7AE |
NEWSTT |
PARTIAL | redirected to RUN command |
$AB1E |
STROUT |
DONE | |
$AD9E |
FRMEVL |
PARTIAL | |
$BDCD |
LINPRT |
DONE | temporary implementation |
$E3BF |
INIT |
NOT DONE | |
$E422 |
INITMSG |
DONE | |
$E453 |
RVECT |
NOT DONE |
NOTE: Even the 'DONE' routines won't support features described as missing in one of the previous chapters!
| Address | Unofficial | Name | Status | Remarks |
|---|---|---|---|---|
($028F) |
KEYLOG |
DONE | ||
$FF81 |
$FF5B |
CINT |
DONE | |
$FF84 |
$FDA3 |
IOINIT |
DONE | |
$FF87 |
$FD50 |
RAMTAS |
DONE | |
$FF8A |
$FD15 |
RESTOR |
DONE | |
$FF8D |
$FD1A |
VECTOR |
DONE | |
$FF90 |
SETMSG |
DONE | ||
$FF93 |
SECOND |
DONE | ||
$FF96 |
TKSA |
DONE | ||
$FF99 |
$FE25 |
MEMTOP |
DONE | |
$FF9C |
MEMBOT |
DONE | ||
$FF9F |
SCNKEY |
DONE | ||
$FFA2 |
SETTMO |
DONE | ||
$FFA5 |
ACPTR |
DONE | ||
$FFA8 |
CIOUT |
DONE | ||
$FFAB |
UNTLK |
DONE | ||
$FFAE |
UNLSN |
DONE | ||
$FFB1 |
LISTEN |
DONE | ||
$FFB4 |
TALK |
DONE | ||
$FFB7 |
READST |
DONE | ||
$FFBA |
SETFLS |
DONE | ||
$FFBD |
SETNAM |
DONE | ||
$FFC0 |
$F34A |
OPEN |
DONE | |
$FFC3 |
$F291 |
CLOSE |
DONE | |
$FFC6 |
$F20E |
CHKIN |
DONE | |
$FFC9 |
$F250 |
CKOUT |
DONE | |
$FFCC |
$F333 |
CLRCHN |
DONE | |
$FFCF |
$F157 |
CHRIN |
PARTIAL | no screen device support |
$FFD2 |
$F1CA |
CHROUT |
DONE | |
$FFD5 |
$F49E |
LOAD |
DONE | |
($0330) |
$F4A5 |
LOAD |
DONE | |
$FFD8 |
$F5DD |
SAVE |
DONE | |
($0332) |
$F5ED |
SAVE |
DONE | |
$FFDB |
SETTIM |
DONE | ||
$FFDE |
RDTIM |
DONE | ||
$FFE1 |
$F6ED |
STOP |
DONE | |
$FFE4 |
$F13E |
GETIN |
PARTIAL | no screen device support |
$FFE7 |
$F32F |
CLALL |
DONE | |
$FFEA |
UDTIM |
DONE | ||
$FFED |
SCREEN |
DONE | ||
$FFF0 |
$E50A |
PLOT |
DONE | |
$FFF3 |
IOBASE |
DONE | ||
($FFFA) |
NMI vec | PARTIAL | ||
($FFFC) |
$FCE2 |
RESET vec | DONE | |
($FFFE) |
IRQ/BRK vec | DONE |
Not all of them - only these we want to have implemented.
| Address | Name | Status | Remarks |
|---|---|---|---|
$E518 |
legacy part of CINT | DONE | |
$E51B |
init screen keyboard, no VIC | DONE | |
$E544 |
clear screen | DONE | |
$E50C |
set cursor position | DONE | |
$E566 |
home cursor | DONE | |
$E56C |
set PNT and USER values | DONE | |
$E5A0 |
setup VIC II & I/O | DONE | |
$E6B6 |
advance cursor | NOT DONE | |
$E701 |
previous line | NOT DONE | |
$E716 |
screen CHROUT | NOT DONE | |
$E8DA |
color code table | DONE | |
$E8EA |
scroll logical line up | DONE | |
$E96C |
insert line on top | NOT DONE | |
$E9FF |
clear line | DONE | |
$EA31 |
default IRQ | PARTIAL | |
$EA7E |
ack CIA1 + below | DONE | |
$EA81 |
ret from IRQ/NMI | DONE | |
$EB48 |
set keyboard mapping table | DONE | |
$F142 |
get key from buffer | DONE | |
$F3F6 |
(unknown) | NOT DONE | |
$F646 |
IEC close | NOT DONE | |
$FD30 |
default vectors | DONE | |
$FD90 |
(unknown) | NOT DONE | |
$FE2D |
memtop set part | DONE | |
$FE47 |
default NMI | PARTIAL | |
$FE66 |
default BRK | DONE | |
$FF80 |
revision byte | DONE |
Note: this is likely to change in the future, possibly in an incompatible way!
| Address | Name | Status | Remarks |
|---|---|---|---|
| ? | MONITOR | WIP | launches a machine language monitor |
| ? | BOOTCPM | WIP | launches the CP/M operating system |
| ? | PRHEX | DONE | print hex value from .A |
$FF7D |
PRIMM | DONE | print immediate, address compatible with C128 and C65 ROMs |
$FFF8 |
DONE | reset vector for usage within hypervisor, starts in legacy mode |