Minimig Board v1.0 schematic

From OpenCircuits
Jump to: navigation, search

Board schematic for Minimig board v1.0:

J1 - Audio output via 3,5mm jack
J4 - 4 bit resistor ladder D/A

In 15kHz mode:

/VSYNC = high (scart RGB enable)
/HSYNC = composite sync
IC5 - FPGA Xilinx XC3S400-4PQ208C
IC3/IC4 - FPGA core power +1,25V +2,5V using LM1117MP-ADJ
J10 - Joystick 0
J6 - Joystick 1
J7 - Jtag
Program & Menu button, 31/15kHz selection, Power & Disc led
J5/J8 - Keyboard & Mouse connections
IC9 - MC68000
MC68000 Decoupling
IC8 - Generation of 4.433619 MHz PAL video MCLK using 74HC4060 (NTSC=3.579545MHz)

PATCH needed to get rev 1 board working:

Disconnect net SPI_DOUT from pin 81 of FPGA.
Connect net SPI_DOUT to pin 19 of FPGA (net USER3).
REASON: Pin 81 is an output during FPGA config that blocks SPI to MMC during startup.
IC10 - MCU PIC18LF252I/SP (DIP28)
IC6/IC7 - Asynchronous static ram 512 x 16 bit (2 chips)
IC2 - Serial RS232 using MAX232A (SO16), output J3
IC1 - Main power supply
J11 - SD Card slot
J9 - Spare I/O directly connected to FPGA

Personal tools
Namespaces

Variants
Actions
Navigation
Toolbox