EXT BUS pinout: Difference between revisions

Latest revision as of 13:40, 28 January 2025

On the back of PC Engine, CoreGrafx, CoreGrafx2, but not Shuttle, 3x23 0.1" pin header

From perspective of someone looking into the back of the console, holding the AV or RF port up, power jack down, and card slot away from you:

Audio-L and Audio-R: analog outputs from the CPU
Audio-C: analog audio mixed in with the above to the mono output for RF or AV OUT
+5A and 0VAG: analog voltage supply for VCE and video amplifier
GND: Digital ground. Notice absence of 5V digital supply.
K7: CPU input for detect CD unit presence
CESEL: VCE input to set /HSYNC, /VSYNC, and DCK to high impedance
/HSYNC, /VSYNC, DCK: VCE-generated video timing signals
HSM: CPU output specifying 7.2MHz operation
/CARD: wire to HuCard slot pin 1, for the CD unit to detect HuCard presence. (Pulled up inside console; expected to be grounded by HuCard)
A0 through A20: CPU address bus
D0 through D7: CPU data bus. (Maybe reversed in Turbografx? Double check)
/WR, /RD, /NMI, /IRQ2, RDY, /RESET: normal CPU signals
/CEK: Asserted by the CPU when it's addressing the VCE
EXTPGW: external unregulated 9V-ish supply, used when nothing's plugged into the barrel jack
VD0 through VD8: raw digital pixel data from VDC to VCE. VD8 also marks sprite pixels.
CompV: Composite video, suitable for direct connection to TV
CSync: Composite sync, 5V levels
VideoR, VideoG, VideoB: raw analog video from VCE with significant DC offset. Unclear if they're rated for enough output current after a DC blocker to be used the same one makes an RGB cable for a megadrive.

Revision as of 13:40, 28 January 2025 (view source) Lidnariq (talk \| contribs) (Created page with "On the back of PC Engine, CoreGrafx, CoreGrafx2, but not Shuttle, 3x23 0.1" pin header From perspective of someone looking into the back of the console, holding the AV or RF port up, power jack down, and card slot away from you: {\| class="wikitable" \|AudioL \|\| AudioC \|\| AudioR \|- \| +5A \|\| K7 \|\| 0VAG \|- \|CESEL \|\| HSM \|\| /CARD \|- \|A18 \|\| /WR \|\| /CEK \|- \|A14 \|\| /NMI \|\| A17 \|- \|A9 \|\| A8 \|\| A13 \|- \|A10 \|\| /RD \|\| A11 \|- \|D6 \|\| D7 \|\| GND \|- \|DCK \|\| D4 \|\| D5 \|- \|/VSYNC \|\| D...")		Latest revision as of 13:40, 28 January 2025 (view source) Lidnariq (talk \| contribs) m (not markdown)
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	On the back of PC Engine, CoreGrafx, CoreGrafx2, but not Shuttle, 3x23 0.1" pin header		On the back of PC Engine, CoreGrafx, CoreGrafx2, but '''not''' Shuttle, 3x23 0.1" pin header

	From perspective of someone looking into the back of the console, holding the AV or RF port up, power jack down, and card slot away from you:		From perspective of someone looking into the back of the console, holding the AV or RF port up, power jack down, and card slot away from you: