Skip to content

Latest commit

 

History

History
139 lines (126 loc) · 6.29 KB

AVRTinyMonitor.md

File metadata and controls

139 lines (126 loc) · 6.29 KB
Raw

ATmega128 Tiny Monitor

The ATmega Tiny Monitor has the following main functions:

  • Control of AVR microprocessor
  • Access to external SRAM shared with Z80
  • Debugging functions for the Z80

As a typical use case, the following commands can be used to download and setup CP/M

  • Write CP/M BIOS to EEPROM. (esave2)
  • Download and boot the INTEL HEX image (cpm22/sys/cpm.ihx) of CP/M. (xload, reset)

Command Reference

Legend

<> is mandatory parameter.
[] is optional parameter.

Memory command

Memory dump

[adr] and [len] are optional. Default values are 0 and 16 respectively.
[adr] is automatically incremented.

command Parameters Memory
d [adr] [len] External SRAM
di [adr] [len] Internal SRAM
df [adr] [len] Flash ROM
de [adr] [len] EEPROM

Byte READ and WRITE

[adr] is optional. Default values is 0. It is automatically incremented.

command Parameters Memory Operation
r [adr] External SRAM READ
w [adr] External SRAM WRITE
ri [adr] Internal SRAM READ
wi [adr] Internal SRAM WRITE

Misc.

command Parameters Memory Operation
f <dat> <adr> <len> External SRAM Fills <dat> into the external memory for length:<len> from the address:<adr>.
test [adr] External SRAM Fill in the memory with test data from specified address:[adr] and verify the checksum.
The default address is 0x2000 if [adr] is omitted.
It is helpful for quick checks of external memory access.
mem Internal SRAM Show remaining memory size. Note that it includes the stack area.

Data transfer command

  • Use esave2 to save the BIOS to EEPROM for automatic CP/M startup.
  • Use xload to download CP/M image (z80/cpm22/sys/cpm.ihx).
command Parameters From To Operation
lx <adr> XMODEM Sender Internal SRAM Load binary image by XMODEM
sx <adr> <len> Internal SRAM XMODEM Reciever Save binary image by XMODEM
bload <adr> XMODEM Sender External SRAM Load binary image by XMODEM
xload XMODEM Sender External SRAM Load INTEL HEX image by XMODEM
The binary is located by being converted from the INTEL HEX format.
eload <dst> <src> <len> EEPROM External SRAM Load EEPROM data from address:<src> for the length:<len> into the external SRAM from the address:<dst>.
esave <dst> <src> <len> External SRAM EEPROM Save External SRAM data from the address:<src> for the length:<len> to the EEPROM from the address:<dst>.
esave2 <dst> <src> <len> External SRAM EEPROM <src> and <len> are stored into EEPROM at address:<dst>.
And save External SRAM data from the address:<src> for the length:<len> to the EEPROM from the address:<dst>+4.

AVR Intterrupt control command

command Parameters Opetarion
cli Disable intrrupt
sti Enable intrrupt

Z80 command

Z80 Control

command Parameters Opetarion
reset [0] Reset Z80. If 0 is specified, HALT instruction(0x76) will be set to 0x0000 and stay in the HALT state.
nmi Assert Z80 /NMI.
int <dat> Assert Z80 /INT. Interrupt the Z80. Depending on the Z80's interrupt mode, is interpreted as follows:
Mode0: Instruction
Mode1: Ignored
Mode2: Interrupt vector number
sts Show the signal state of /BUSREQ, /BUSACK and /HALT.

Z80 Debugger

command Parameters Opetarion
brk [adr] Set breakpoint. List breakpoints if [adr] is omitted.
del <adr> Delete breakpoint.
cont Continue program after break.
  • Example 
    >brk $f3dd
>brk
0: $f3dd $c3
    Z80 registers and stack data are shown when hit the breakpoint. 
    >>>>Break! at $f3dd
AF=$0044 [Z:1 C:0] I=$f3
BC=$0000 DE=$dc06 HL=$f233
IX=$efff IY=$fd77 SP=$dbfe
(SP+0)=$f3dd
(SP+2)=$5cc3
(SP+4)=$c3df

Help command

command Parameters Opetarion
h Shows help message.
  • Example 
    ATmega128 Tiny Monitor
>h 
<> : mandatory
[] : optional
$  : Prefix of hexadecimal
h               : Help
== AVR Commands ==
r  [adr]        : Read  an ExtRAM byte
ri [adr]        : Read  an IntRAM byte
w  <adr> <dat>  : Write an ExtRAM byte
wi <adr> <dat>  : Write an IntRAM byte
f  <dat> <adr> <len> : Fill ExtRAM with <dat>
d  [adr] [len]  : Dump ExtRAM
di [adr] [len]  : Dump IntRAM
df [adr] [len]  : Dump FlashROM
de [adr] [len]  : Dump EEPROM
lx <adr>        : Load binary to   IntRAM by XMODEM
sx <adr> <len>  : Save binary from IntRAM by XMODEM
bload <adr>     : Load binary    to ExtRAM by XMODEM
xload           : Load INTEL HEX to ExtRAM by XMODEM
eload <dst> <src> <len>  : Load EEPROM to ExtRAM
esave  <dst> <src> <len> : Save ExtRAM to EEPROM
esave2 <dst> <src> <len> : esave after writing <src> <len>
mem             : Remaining IntRAM size
sei             : Set  interrupt
cli             : Clear interrupt
test [adr]      : Test XMEM R/W
== Z80 Control Commands ==
reset [0]       : Reset, HALT if 0
nmi             : Invoke NMI
int <dat>       : Invoke interrupt
sts             : Show Z80 status
== Z80 Debug Commands ==
brk [adr]       : Set breakpoint, show list if no adr
del <adr>       : Delete breakpoint
cont            : Continue from breakpoint