That's a weird IP address. Are you connecting the Macs directly together? I have my G5 connected to a Ethernet switch which is connected to a router which is the cable modem. I boot the G5 and look at the network settings to see what IP address was assigned by DHCP. Then I use that IP address in Open Firmware.
What version of telnet are you using? What Mac and macOS version are you using for telnet? I use Monterey on my MacPro3,1.
Before doing do-map, check the list of translations
For 64 bit CPUs:
Code:
dev /cpus/@0
cr " translations" active-package get-package-property 0= if bounds do i @ u. i 4+ @ u. i 8 + @ u. i c + @ u. i 10 + @ u. cr 14 +loop then
For 32 bit CPUs:
Code:
dev /cpus/@0
cr " translations" active-package get-package-property 0= if bounds do i @ u. i 4+ @ u. i 8 + @ u. i c + @ u. i cr 10 +loop then
The translations show:
32-bit virtual address, 32-bit size, 32 or 64 bit physical address, mode
It is possible to map the same physical address to multiple virtual addresses.
The do-map command is defined like this (32-bit physical and virtual addresses)
Code:
: do-map ( phys virt size mode -- )
\ mode is one of these:
40 constant w___ \ Write-through
28 constant _i_g \ Cache-Inhibited, Guarded
10 constant __m_ \ Memory-coherent
Try this (after making sure there's no translation for virtual address 40000000 already):
Code:
: dumpbytes bounds ?do i 3f and 0= if cr then i c@ 2 u.r loop cr ; ok
fff00000 40000000 100000 28 do-map ok
40000000 100000 dumpbytes