[sebhc] Emulator fixes / additions

Steven Parker sp11 at hotmail.com
Wed May 26 18:52:17 CDT 2004


Before I forget, Dwight found a pristine HDOS 1.0 image .. I put it in the 
disk-images.  He also sent me 2 bootable images with basic games .. they are 
chase.h8d and bgames.h8d under "other".

Anyway, Dave was saying:
>OK - I have implemented this - a HLT with interrupt disabled just freezes

I assume you mean "enabled".  It does seem to work now.

>   we could easily turn them OFF, and allow all of memory to be RAM -
>   currently no I/O port for doing this, but it could be easily added.

Wow, you are really close to having the XCON configuration implemented.

>   [Unfortuntely, you can't do this when starting the simulator because 
>PAM-8
>    dies if all memory is RAM - its "find end of memory" test wraps to 0000
>    and it continues forever]

Even with XCON, on reset you need to switch the rom(s) back on.  After the 
I/O port, the only other thing you'd need for XCON is a way to set the boot 
control switch positions that it reads (cmd line parms?).  I attached a 
mtr.acm excerpt to the end of this mail with the port and bit definitions.

>   Not why you would want to do this, but if you need to eliminate some RAM
>   from the expansion area, this will let you do it.

Well, it lets you prove the distribution sw really runs in minimal memory 
configurations.  :-)

>- I've made the H17 optional. Basically, the H17 ROM and I/O ports ...

...and the H17 write-protectable RAM?

>   At some point I'll create a custom library for my Micro-C/PC compiler 
>which
>   will let you write virtual I/O devices in 'C'.

How cool!  And will it also have access to the H8 memory (DMA)?  Doesn't 
need to get invoked on access, but just read/write it when it DOES run.

Cheers,

- Steven

==========================================================

**      I/O Ports
*
IP.CON  EQU     362Q            H-88/H-89/HA-8-8 Configuration
OP2.CTL EQU     362Q            H-88/H-89/HA-8-8 Control Port

**      Front Panel Control Bits
*
*       CB2.* set in OP2.CTL
*
CB2.SSI EQU     00000001B       Single Step Interrupt
CB2.CLI EQU     00000010B       Clock Interrupt Enable
CB2.ORG EQU     00100000B       ORG 0 Select
CB2.SID EQU     01000000B       Side 1 Select

**      Configuration Flags
*
*       These bits are read in IP.CON
*
CN.174M EQU     00000011B       Port 174Q Device-Type Mask
CN.170M EQU     00001100B       Port 170Q Device-Type Mask
CN.PRI  EQU     00010000B       Primary/Secondary:  1=>primary == 170Q
CN.MEM  EQU     00100000B       Memory Test/Normal Switch:  0=>Test; 
1=>Normal
CN.BAU  EQU     01000000B       Baud Rate:  0=>9600; 1=>19,200
CN.ABO  EQU     10000000B       Auto-Boot:  1=>Auto-Boot

CND.H17 EQU     00B             H-17 Disk,            Valid only in CN.174M
CND.NDI EQU     00B             No Device Installed,  Valid only in CN.170M
CND.H47 EQU     01B             H-47 Disk

==========================================================

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