MAX6921 Shift Register
-------------------------------------------------------------------------------
-This is a capture of data output to a MAX6921 high voltage shift register that
-was outputting data for a VFD clock.
+This is a capture of data output to a Maxim MAX6921 high voltage shift
+register that was outputting data for a VFD clock.
The signals were grabbed on a 28-pin PLCC chip (MAX6921) which outputs 20-bits
that is crafted as a design for VFD applications.
+Details:
+ - BeagleBoard.org vendor tree: https://github.com/beagleboard/kernel
+ - Beagle Nixie GitHub: https://github.com/mranostay/beagle-nixie/
+ - MAX6921 datasheet: http://datasheets.maximintegrated.com/en/ds/MAX6921-MAX6931.pdf
+
+
Logic analyzer setup
--------------------
-The logic analyzer used was Open Bench Logic Sniffer (at 10Mhz):
+The logic analyzer used was Open Bench Logic Sniffer (at 10MHz):
- Probe MAX6921 Pin
+ Probe MAX6921 pin
--------------------------
- 0 LOAD
+ 0 LOAD
1 DATA
2 CLK
3 BLANK (PWM Brightness Control)
+
Data
----
prototype Nixie Cape for the Beaglebone.
Digit Bit
- --------------------------
- 0 1<<12
- 1 1<<19
- 2 1<<13
- 3 1<<18
- 4 1<<14
- 5 1<<17
- 6 1<<16
- 7 1<<15
- 8 1<<15
- 9 1<<11
+ -----------------------
+ 0 (1 << 12)
+ 1 (1 << 19)
+ 2 (1 << 13)
+ 3 (1 << 18)
+ 4 (1 << 14)
+ 5 (1 << 17)
+ 6 (1 << 16)
+ 7 (1 << 15)
+ 8 (1 << 15)
+ 9 (1 << 11)
Segment Bit
- ---------------------------
- SEG_A 1<<0
- SEG_B 1<<1
- SEG_C 1<<2
- SEG_D 1<<3
- SEG_E 1<<4
- SEG_F 1<<5
- SEG_G 1<<6
- SEG_H 1<<7
-
-
-References:
------------
-
- * BeagleBoard.org Vendor Tree (https://github.com/beagleboard/kernel)
- * Beagle Nixie GitHub (https://github.com/mranostay/beagle-nixie/)
- * MAX6921 Datasheet (http://datasheets.maximintegrated.com/en/ds/MAX6921-MAX6931.pdf)
+ -----------------------
+ SEG_A (1 << 0)
+ SEG_B (1 << 1)
+ SEG_C (1 << 2)
+ SEG_D (1 << 3)
+ SEG_E (1 << 4)
+ SEG_F (1 << 5)
+ SEG_G (1 << 6)
+ SEG_H (1 << 7)
The sigrok command line used was:
- sigrok-cli --driver=ols:conn=/dev/ttyACM0 -d samplerate=10mhz \
- -samples=24576 -p 0=LOAD,1=DATA,2=CLK,3=BLANK -o max6921_data_10mhz.sr
+ sigrok-cli --driver=ols:conn=/dev/ttyACM0 -d samplerate=10mhz \
+ --samples=24576 -p 0=LOAD,1=DATA,2=CLK,3=BLANK -o <filename>