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Yamaha S3527
This page was last modified 18:41, 24 September 2023 by Mars2000you. Based on work by Gdx and Lintweaker and others.

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Description

Yamaha S3527

The S3527 (aka MPC) is a chipset called MSX-SYSTEM made by Yamaha for ASCII & Microsoft. It has the following features:

  • a Yamaha YM2149 PSG-sound chip, compatible with a General Instrument AY-3-8910 (for sound, joystick ports, etc)
  • PPI: backward compatible with the Intel i8255 (primary and some secondary slot selection, keyboard (keypad included), cassette interface, etc)
  • other MSX functions: DRAM/ROM control, printer interface, etc.
  • 100 pins

Notes:

  • the S3527 is used in several MSX2 machines. In case of RTC and optional MSX2 features, these are implemented using additional IC's.
  • it has been preceded by the X3527, used in the Yamaha CX11 computer
  • Undocumented feature: All 3 PPI ports (0A8-0AAh) and control port (0ABh) are mirrored to I/O ports 0AC-0AFh. This can be used to determine if a machine has an MSX-ENGINE.
  • The S3527 makes a mirror of VDP ports 98h-9Bh to 9Ch-9Fh.

S3527 Pinout

Pin Name Type Active Function
1 CMI I Read signal input from cassette tape
2 CMO O Write output to cassette tape
3 REM O Cassette control signal output (motor ON/OFF control)
4 PRISND O Software-controlled sound output
5 SSGSND O PSG analog sound output
6 Vss PSG ground (0V)
7 VDPCW O VDP (Video Display Processor) write timing signal output
8 VDPCR O VDP read timing signal output
9 RSEL I △ Slot expansion address input
10~18 AB15~AB0 I Z80A CPU address bus input (9 bits) (AB15, A814, AB7, AB6, AB5, A84, AB3, AB1, ABO)
19~26 DB7~DB0 I/O Z80A CPU data bus I/O (8 bit)
27 SLT03/33 O Expanded slot #03 or #33 select signal
28 SLT01/31 O Expanded slot #01 or #31 select signal
29 ϕOUT O Z80A CPU clock output
30 ϕIN I Clock input (This signal is used via a buffer for clock input to other than the Z80A).
31 Vss 0V ground
32 RSTO O Slot expansion initialization signal input
33 RSTI I △ Slot expansion initialization signal input (RESET signal input)
34 M1 I Z80A CPU M1 input
35 RFSH I Z80A CPU RFSH input
36 MREQ I Z80A CPU input
37 IORQ I Z80A CPU IORQ input
38 RD I Z80A CPU RD input
39 RW I Z80A CPU WR input
40 VDD +5V power supply
41 WAIT O △/▽ 1WAIT request signal output in Ml cycle (Wired logic with external WAIT signal possible)
42 ROMCS O MSX BASIC ROM select signal output
43 RAS O D-RAM RAS signal output (with Z80 RAS only refresh function)
44 MPX O D-RAM address multiplex signal output
45 CAS3 O D-RAM CAS signal output (CAS3: SLOT #0 or #00 C000h~FFFFh)
46 CAS2/E O D-RAM CAS signal output (CAS2/E: SLOT #0 0000h~FFFFh or #00 0000h~FFFFh / SLOT #02 0000h~7FFFh or #32 0000h~FFFFh)
47 WE O D-RAM write enable signal output
48 FWD 1 △ I Joystick FWD 1 signal / general-purpose port input
49 BACK 1 △ I Joystick BACK 1 signal / general-purpose port input
50 LEFT 1 △ I Joystick LEFT 1 signal / general-purpose port input
51 RIGHT 1 △ I Joystick RIGHT 1 signal / general-purpose port input
52 TRGA 1 I/O △/▽ Joystick TRGA 1 signal / general-purpose port output (I/O by wired logic
53 TRGB 1 I/O △/▽ Joystick TRGB 1 signal / general-purpose port output (I/O by wired logic)
54 STB 1 O General-purpose port 1 strobe
55 FWD 2 I △ Joystick FWD 2 signal / general-purpose port input
56 BACK 2 I △ Joystick BACK 2 signal / general-purpose port input
57 LEFT 2 I △ Joystick LEFT 2 signal / general-purpose port input
58 RIGHT I △ Joystick RIGHT 2 signal / general-purpose port input
59 TRGA 2 I/O △/▽ Joystick TRGA 2 signal / general-purpose port output (I/O by wired logic)
60 TRGB 2 I/O △/▽ Joystick TRGB 2 signal / general-purpose port 001001 (I/O by wired logic)
61 STB 2 O General-purpose port 2 strobe
62 Y10/SK O/I △/▽ It becomes a serial key input pin (SK) depending on the function selection during reset (1 bit) (unused by CX-5M II)
63 JIS/50 I △ Keyboard layout control input
64 CAPS O ▽ CAPS LED control signal output (Direct supplying of LED possible)
65 CODE O ▽ CODE LED control signal output (Direct supplying of LED possible)
66~73 X0~X7 I △ Keyboard return signal input (8 bits) (X6 nad X7 serve as function select input on a reset)
74~83 Y0~Y9 O ▽ Keyboard scanning signal output (10 bits)
84 CS1 O ROM select signal output (4000h~7FFFh)
85 CS2 O ROM select signal output (8000h~BFFFh)
86 CS12 O ROM select signal output (4000h~BFFFh)
87 SLT1 O Slot select signal output (SLOT #1)
88 SLT2 O Slot select signal output (SLOT #2)
89 SLT3/30 O Slot#3 or #30 select signal output
90 VDD +5V power supply
91 BUSY I △ Printer status input
92~99 PD87~PD80 O Print data output (8 bits)
100 PSTB O Printer strobe output

△ = with 22KΩ resistor pull up
▽ = Open drain (pull down) output

Computers with the S3527

Links

Retrieved from "https://www.msx.org/wiki/Yamaha_S3527"