TI SR-16 II

Chip labeled 
TMS1016NL
A ^ 7537

die labeled
1016A

31 buttons: 0-9, ., +/-, +, -, *, /, =, CD, EE, Pi, STO, RCL, sum, e^x, lnx, y^x, 1/x, sqrt, x^2, log, C
12 7-segment LEDs, digits 3 and 12 (from the right) only display segment G (digit 12 G is O6, digit 3 G is O1)


TMS1000 pinout

1  R8   - digit 10 and button matrix
2  R9   - digit 11 and button matrix
3  R10  - digits 3 and 12 and button matrix
4  VDD
5  K1   - button matrix
6  K2   - button matrix
7  K4   - button matrix
8  K8   - button matrix
9  INIT - VDD
10 O7   - DP segments
11 O6   - segment G
12 O5   - segment F
13 O4   - segment E
14 O3   - segment D
15 O2   - segment C
16 O1   - segment B
17 O0   - segment A
18 OSC1 - OSC2 and 100 cap to VSS, 30K resistor to VDD
19 OSC2 - OSCa and cap and resistor
20 VSS
21 R0   - digit 1 and button matrix
22 R1   - digit 2 and button matrix
23 R2   - digit 4 and button matrix
24 R3   - digit 5 and button matrix
25 R4   - digit 6 and button matrix
26 R5   - digit 7 and button matrix
27 R6   - digit 8 and button matrix
28 R7   - digit 9 and button matrix


button matrix

        K1          K2           K4         K8
R0     xxxx         C           xxxx       xxxx
R1     xxxx        xxxx          CD         0
R2     xxxx        xxxx         xxxx        1
R3     xxxx        xxxx         +/-         2
R4     x^2         xxxx         xxxx        3
R5     log         xxxx          EE         4
R6     sqrt         +            .          5
R7     lnx          -           STO         6
R8     1/x          X           RCL         7
R9     e^x          /           SUM         8
R10    y^x          =           Pi          9