*** Registers
GR0 *always zero
GR1 scratch
GR2 normal return register
GR27 Global Data Pointer (Must be set in crt0)
GR30 SP stack pointer
GR31 milicode return pointer
SR* Space registers
CR24-31 Temporary Control Registers
CR14 Vector Table Register (like VBR on an m68020)
CR0 Put in a count, causes exception when decremented to 0.
FORTH's magic number is 031240
***
Series 700/800
The following options are also supported:
-snnn set the initial system load (ISL) start address to
nnn in the volume label. This is useful when
building boot media for Series 700/800 systems.
-lnnn specifies the length in bytes of the ISL code in
the LIF volume.
-ennn set the ISL entry point to nnn bytes from the
beginning of the ISL. For example, specifying -
e3272 means that the ISL entry point is 3272
(decimal) bytes from the beginning of the ISL
object module.
-Knnn forces the directory start location to be the
nearest multiple of nnn x 1024 bytes from the
beginning of the volume. This is necessary for
booting Series 700/800 systems from LIF media.
-n xxx Sets the volume name to be xxx.
lifinit -v64000000 -d64 -nISL10 -K2 -s4096 -l61440 -e5336 this_lif
# lifcp --
# -r Forces RAW mode copying. (file type BIN (-23951))
# -T Sets the file type of the directory entry.
# -Knnn forces each file copied in to begin on a nnn x
# 1024-byte boundary from the beginning of the volume
# Note: the word echoed below MUST be 10 characters exactly.
#
(echo "FORTH ") | lifcp -r -T-030001 -K2 - this_lif:AUTO
#
# somxtract infile outfile --
# converts a series 800 file *only* into a raw image
It turns out the native cc and our current gcc produce series 700
output, so in this case it runs till if fills up the hard disk.
*** rombootlf5 is a FORTH interpreter in a "boot" image. (it won't run on
the HP742 board)
lifls -l rombootlf5
volume ISL10 data size 249984 directory size 8 94/04/20 10:26:36
filename type start size implement created
===============================================================
ISL -12800 16 240 0 94/04/20 10:26:36
HPUX -12928 256 496 0 94/04/20 10:26:37
IOMAP -12960 752 1504 0 94/04/20 10:26:37
AUTO -12289 2256 1 0 94/04/20 10:26:38
FORTH -12960 2264 208 0 94/04/20 10:26:38
HPFORTH ASCII 2472 420 0 94/04/20 10:26:38
BOOTROM ASCII 2896 3849 0 94/04/20 10:26:40
PAD1 -12290 6752 1172 0 94/04/20 10:26:40
*** The ISL is only needed when booting the raw hardware. As we're runing
on a monitor (barely) all we need is a crt0 that initiallizes the GR27
Global Data Pointer and zero's bss.
*** Initial Program Load
--------------------
From page 11-56, architecture book.
0x00000000 +------------------------------------+ 0
| LIF_MAGIC | |
0x00000004 +------------------------------------+ 4
| |
0x000000F0 +------------------------------------+ 240
| IPL_ADDR |
0x000000F4 +------------------------------------+ 244
| IPL_SIZE |
0x000000F8 +------------------------------------+ 248
| IPL_ENTRY |
0x000000FC +------------------------------------+ 252
| |
IPL_ADDR +------------------------------------+ IPL_ADDR
| Position Independant |
| IPL Code |
| (including IPL_CHECKSUM) |
+------------------------------------+ IPL_ADDR + IPL_SIZE
| |
+------------------------------------+
IPL_ADDR 2 Kbyte aligned, nonzero
IPL_SIZE Multiple of 2Kbytes, <= 256 Kbytes
IPL_ENTRY Word aligned, less than IPL_SIZE
Loads at IPL_START
This is based on Cobra/Coral hardware:
LED register at 0xf080024
I/O status register at 0xf0800000
EEPROM at 0xf0810000 (LAN ID begins at byte 0)
Here's a dump of the LIF volume header using "xd" (od with hex output)
*
00000f0 0000 1000 0000 9800 0000 0000 0000 0000
^^^^
This is the size
*
0000800 5445 5354 2020 2020 2020 a271 0000 0010
^^^^ ^^^^ ^^^^ ^^^^ ^^^^ ^^^^<-- this is the ipl offset
this is the vol name ^^^^<- this is the type
0000810 0000 0098 9407 1919 1426 8001 0000 0000
^^^^
This is the ipl size
Interupts
---------
The vector table is access by %iva (%cr14). The address here must be a
multiple of 2048. The indexes are:
1 high-priority
2 power failure
3 recovery counter
4 external interrupt
5 low-priority machine check
6 instruction TLB miss/instruction page fault
7 instruction memory protection
8 illegal instruction
9 break instruction
10 priviledged operation
11 priviledged register
12 overflow
13 conditional
14 assist exception
15 data TLB miss fault/data page fault
16 non access instruction TLB miss fault
17 non access page TLB miss fault/non access data page fault
18 data memory protection/unaligned data reference
19 data memory break
20 TLB dirty bit
21 page reference
22 assist emulation
23 higher-priority transfer
24 lower-priority transfe
25 taken branch
502cf4b7b5