Avoid connecting or disconnecting anything to the V6Z80P whilst the power is switched on (SD cards shouldn't be a problem, but FLOS cannot automatically recognize card swaps so any card inserted whilst the power is on needs to be initialized with the “MOUNT” command).\
If you have any problems formatting an SD card to FAT16 on the PC, try doing it under FLOS with the command:
You can create a multi-volume SD card if you wish by using the FLOS utility DISKTOOL. This can make up to 4 partitions using the 4 slots in the Master Boot Record. Note however, that Windows (XP) will only see the first partition since it uses a different scheme for partitioning. (Linux will generally see all the FLOS partitions).
Incompatibilies: Some old versions of FLOS may not work with new versions of OSCA and vice versa. If you have any problems updating the system with EEPROM, please use the utility UPDATE - it can be loaded from SD card as any other command or sent to the V6Z80P via Serial Link (Enter:
RX * 5000, wait for it to download, then enter
Whilst the Windows GUI “Serial Link” is useful for occasional file transfers, it may be more convenient to use “SerialTX”. This is a console / command line based utility (found in the project's “PC-based Apps” folder) which can send files from other programs etc, via “open with” etc. It can also be handy to copy FileTX to Windows' “Send To” list so that files can be send via a right click →Send To.
The default sound set-up of OSCA is stereo separation. If you prefer mono output (which sends all 4 channels to both side, also increasing the overall volume) add the line MONO to the BOOTRUN.SCR file in the root of the SD Card.
There are two reset jumpers on the V6Z80P. The first (in the 10-pin header group) is merely a programmable FPGA pin - in OSCA this can be used to reset the Z80 CPU. The second, “J2” can be used in all configs to reconfigure the FPGA to whichever is the power-on boot slot. Therefore a button across J2 can be used to return from the
Spectrum Emulators to OSCA without physically powering off the board (note: for J2 to exhibit this behavior, the PIC firmware version needs to be v637+)
If your PC does not have a 9 pin serial connector, a USB serial adapter should work fine. The “Prolific” chipset cables (about £2-£10 on eBay) are known to work well, but make sure you get the latest drivers.
A modern USB keyboard can be used if it came with a PS/2 adapter but some of these keyboards have unusual / slow start up sequences. If you encounter problems, create a text file in the root of your SD card called SYSTEM.CFG containing the line RESETKB=0. (The default bootloader action is to reset the keyboard and wait for acknowledgement). The total power the V6Z80P can delivery to the keyboard and mouse in total is about 100mA, so check the power consumption of your devices (it'll normally be stated on the label).
The default keymap used by FLOS is that of the UK but this can be changed with the KEYMAP command. Keymaps for Germany, France, Italy, Portugal and USA are supplied and an editor is provided (KMAPEDIT) to make others.
Essentially, these are wired as per the standard Atari 2600 style. The second fire button is connected to pin 9 (same as on the Amiga). Pin 5 is connected to 3.3volts (via a small resistor (22ohm) so can provide a little power - this should allow Megadrive pads to be used too). Pin 7 is unconnected.
It has been found that some ultra-cheap cards do not work in the V6Z80P (and other hobbyist project boards). Good brand MMC, SD and SDHC cards should all work.
If the FPGA does not receive a valid configuration pattern from the EEPROM upon power on, the status LED will flash slowly (around 1 flash per second). There are various ways to fix this:
Assuming there is a working config in Slot 1 - 7 and the problem is just that the Power-On Boot Slot selection is pointing at a bad config:
JTAG configuration - requires suitable Xilinx JTAG cable.
With Config PIC firmware v616+ the Active Slot can be changed manually. Assuming there is a working config in Slot 1, 2 or 3 and the problem is just that the power on boot slot selection is pointing at a bad config:
Remove and reprogram the EEPROM or config PIC externally.
It is the PIC chip that actually holds the slot selection - you will only need to reprogram the PIC if you have old firmware that doesn't support the manual slot selection. If you do reprogram the PIC, use the latest firmware .hex file so that you wont have to do so again. If you reprogram the EEPROM, use “default.bin” from the folder development_files/v6z80p/eeprom this also contains the bootcode for SLOT 0.
JTAG config. If none of the first 3 slots contain OSCA:
Once the FPGA has sucessfully configured, its internal ROM attempts to load the system bootcode, which should be located on the onboard EEPROM. If there is a problem, the screen flashes magenta and after trying again, it turns grey. At this point a bootcode file (EG: bootcode.epr) can be downloaded via the serial link (must be 115KBPS). The grey screen condition can also be forced by holding up, right and fire on a joystick in Port 1
at power up. Once FLOS is loaded, the bootcode file can be replaced on the EEPROM using the utility EEPROM.FLX
An OSCA/FLOS emulator for Windows (by Tony Friery) is available in the Contributions/Tony. This has progressed far enough to allow simple FLOS programs to be tested on the PC. Bear in mind that timing is currently not perfect and certain elements of OSCA (EG: line draw) are not yet emulated.