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====== Getting Started with ZRC ======

===== Introduction =====

This instruction describes the process of getting ZRC powered up and running ROMWBW.

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ZRC is a Z80 SBC that requires a terminal emulator running on PC connected to ZRC via an USB cable and regulated 5V, 150mA power via a 2.1mm X 5.5mm power plug. The setting on the terminal emulator is 115200 N-8-1 with hardware RTS/CTS handshake.

Once power is applied (or when reset button is pressed and released), ZRC will output a countdown sequence on the serial port “987650321” in about 4 seconds. At the end of the countdown, ZRC will load and execute the bootstrap program in the Master Boot Record of the compact flash disk. If CF disk is not present, ZRC will jump to RAM location 0xb000. During the 4-second countdown period, a 256-byte binary program can be loaded into the serial port. ZRC will load the 256-byte program in RAM location 0xb000 to 0xb0ff and start program execution at 0xb000 when the 256th byte of serial data is received.

The ZRC as delivered is assembled, tested, and loaded with necessary software to run ROMWBW. When power is initally applied, ZRC will display the countdown sequence of “987650321” and then it will load the CF bootstrap program which, in turn, will load the ZRCMonitor. The following is the power on message:

<code code>
987650321ZRC Monitor v0.4c 7/17/20
</code>

Type 'h' at ZRC Monitor prompt to display the help menu. Additional documentation about the various ZRC Monitor commands can be found in ZRC Monitor manual <– need work

<code code>
>help
G <addr> CR
R <track> <sector>
D <start addr> <end addr>
I <port>
O <value> <port>
L <start addr> <end addr>
Z CR
F CR
T CR
E <addr>
X <options> CR
B <options> CR
C <options> CR
</code>

The command to run ROMWBW is 'b4' which will load 512K image from CF disk into memory and transfer control to 0x0

<code code>
>boot CP/M
1--User Apps,
2--CP/M2.2:
3--CP/M3:
4--ROMWBW: 4 press Return to execute command
hë

RomWBW HBIOS v3.1.1-pre.21, 2020-07-03

RC2014 Z80 @ 7.372MHz
0 MEM W/S, 1 I/O W/S, INT MODE 1
512KB ROM, 512KB RAM

ACIA0: IO=0x80 ACIA MODE=115200,8,N,1
DSRTC: MODE=STD IO=0xC0 NOT PRESENT
MD: UNITS=2 ROMDISK=384KB RAMDISK=384KB
IDE: IO=0x10 MODE=RC
IDE0: 8-BIT LBA BLOCKS=0x0001E900 SIZE=61MB
IDE1: NO MEDIA
PPIDE: IO=0x20 PPI NOT PRESENT

Unit        Device      Type              Capacity/Mode
----------  ----------  ----------------  --------------------
Char 0      ACIA0:      RS-232            115200,8,N,1
Disk 0      MD1:        RAM Disk          384KB,LBA
Disk 1      MD0:        ROM Disk          384KB,LBA
Disk 2      IDE0:       CompactFlash      61MB,LBA
Disk 3      IDE1:       Hard Disk         --

RC2014 Boot Loader

Boot [H=Help]:
</code>