2.0 KiB
The Cricket! - ProDOS Clock Driver
I acquired a Cricket sound/clock peripheral on eBay. Therefore it is now critical that we have a conforming ProDOS clock driver for it.
STATUS: Works on my machine!
Background
"The Cricket!" by Street Electronics Corporation, released in 1984, is a hardware peripheral for the Apple //c computer. It plugs into the serial port and offers a multi-voice sound synthesizer, a speech synthesizer, and a real-time clock.
The disks supplied with the device include:
/CRICKET/PRODOS.MOD
which can be BRUN to patch ProDOS in memory with a clock driver.- A modified version of ProDOS
- A utility to patch ProDOS on disk
Goals
Like the NS.CLOCK.SYSTEM
(by "CAP") ideally we would have:
- A ProDOS
.SYSTEM
file - Detects the presence of a Cricket
- Installs a driver in memory following the ProDOS clock driver protocol
- Chains to the next
.SYSTEM
file (e.g.BASIC.SYSTEM
)
Successfully tested on real hardware. (Laser 128EX, an Apple //c clone — including at 3x speed!)
Build
Requires cc65. The included Makefile
is very specific to my machine - sorry about that.
CRICKET.SYSTEM is the result of the build.
Notes
I ended up disassembling both NS.CLOCK.SYSTEM (to understand the SYSTEM chaining - what a pain!) and The Cricket!'s PRODOS.MOD and melding them together, adding in the detection routine following the protocol in the manual.
Other files:
- GET.TIME just prints the current ProDOS date/time, to verify the time is set and updating.
- TEST attempts to identify an SSC in Slot 2 and the Cricket via the ID sequence, to test routines.
Resources
Cricket disks on Asimov:
- ftp://ftp.apple.asimov.net/pub/apple_II/images/hardware/sound/cricket_disk1.po
- ftp://ftp.apple.asimov.net/pub/apple_II/images/hardware/sound/cricket_disk2.po
Cricket Manual on Asimov:
- ftp://ftp.apple.asimov.net/pub/apple_II/documentation/hardware/sound/Street%20Electronics%20The%20Cricket.pdf