Differences

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--- info:verifone_tranz_330_hacking [2008/08/16 23:30] – created tomgee
+++ info:verifone_tranz_330_hacking [2008/08/18 11:33] (current) – tomgee
@@ Line 30: / Line 30: @@
 That leaves 5 pins unaccounted for.
 ==== Header Block Pinout ====
@@ Line 42: / Line 43: @@
   Pin  7 - Column 2 of the keypad
   Pin  8 - Column 1 of the keypad
+  Pin 12 - pulses when card swiped as seen by TG
   Pin 13 - /POR on the OKI display chip.  Set this low for
 ns to reset the chip.
@@ Line 50: / Line 52: @@
   Pin 20 - GND for the board.
+==== Display ====
+Thing thing has an awesome 16 character 16-segment VFD display with a OKI C1937-01 display driver.
+It's a pretty standard shift register thing to get data into it, except that it reads DATA when SCLK goes _LOW_ instead of HIGH. Also, there's no LATCH. You have to be very careful about clocking it data, I guess?
+To write to the display, you clock in "00" followed by 6 bits of value. 0x00 is "@". Actually, you can use ASCII values, sent through a "if (val > 63) val -= 64;" filter.
+Power Consumption: OKI + VFD == 55-60mA
+==== API ====
+Okay, so I have a pretty simple API in place now..
+    * resetOki - Resets the controller IC
+    * setPosition - Sets the cursor to a certain position.
+    * writeChar - Takes an ASCII character, displays it on the screen.
+    * setBrightness - Sets the duty cycle (brightness).
+    * printString - A generic print that prints a series of letters on the screen.
+    * cyclon - Make a character go back and forth across the screen.
+Still needed:
+    * Fade special effect (just calls setBrightness at a specified rate).
+    * Scroll special effect. Scroll a message across the screen at a specified rate and direction.
+==== Keypad ====
+This looks like a standard matrix keypad. To read, you just activate the columns one by one, and see which (if any) of the row pins light up. Pins 1-8 of the header are the keypad.
+Tie this to a timer interrupt, and you'll always have an uint16_t with the active buttons listed in it. (Er.. Overly complex. Just poll it when you need it.)
+==== Speaker ====
+A Piezo Buzzer, connected to pin 18.
+==== Mag stripe reader ====
+Man, NO idea. This is utter magic to me.
+Is it a high and low value? Does it need an op-amp? There are a bunch of op-amps on the board. Maybe one of them?
+How is data encoded?